JP2015106957A - Charging apparatus - Google Patents

Abstract

Provided is a charging device that extends the life of a secondary battery. A charging device for charging a secondary battery housed in a battery pack, wherein the battery pack includes a corresponding value calculating means for calculating a corresponding value corresponding to a charging capacity of the secondary battery, and a corresponding value. And a storage device that stores each time the battery is charged, and the charging device acquires a corresponding value, a condition setting unit that sets a charging condition based on the corresponding value, and charges the secondary battery using the charging condition. Charging control means for controlling. [Selection] Figure 2

Description

  The present invention relates to a charging device, and more particularly to a charging device suitable for charging a secondary battery used as a power source for a cordless power tool.

  2. Description of the Related Art Conventionally, battery packs that contain secondary batteries used as power sources for various electrical devices and charging devices for charging secondary batteries contained in battery packs have been widely used. Various solutions have been proposed for various problems that occur when the secondary battery in the battery pack is used.

  For example, in a lithium-ion battery whose capacity is increasing, it is charged at a predetermined constant current value after being charged at a predetermined constant current value, and the charging is terminated when the predetermined end current value is reached. Although control is generally performed, there is a battery in which the influence of charging conditions such as a constant voltage value and a termination current value on the lifetime tends to be greater than that of a conventional battery as the capacity increases. The battery has a problem that the life of the secondary battery is shortened when the charging is repeated only under the charging condition for completing the charging in a short time with a high capacity.

  In order to solve the above problem, a charging device has been proposed in which a constant voltage value in constant current constant voltage charging control can be set low (Patent Document 1).

JP 2008-187790 A

  However, in the above charging apparatus, the user has to select a normal mode in which the constant voltage value is set to the maximum charging voltage and a long life mode in which the constant voltage value is set lower than the normal mode. It was. In general, it is known that the influence of the charging condition on the lifetime becomes larger as the deterioration degree of the secondary battery becomes higher. However, the charging condition such as a constant voltage value is set according to the deterioration degree of the secondary battery. Therefore, the secondary battery with a high degree of degradation and the secondary battery with a low degree of deterioration are charged under the same charging conditions, and the secondary battery with a high degree of deterioration is fixed. There is a problem that the deterioration is further advanced, which is incomplete in order to extend the life of the secondary battery.

  Therefore, the present invention automatically determines the degree of deterioration of the secondary battery, sets the charging condition according to the degree of deterioration, and performs charging while reducing the burden on the secondary battery during charging using the charging condition. Then, it aims at providing the charging device which aimed at the lifetime improvement of the secondary battery which reduced the effort of a user.

  In order to solve the above problems, the present invention is a charging device for charging a secondary battery housed in a battery pack, and the battery pack calculates a corresponding value corresponding to the charging capacity of the secondary battery. Correspondence value calculation means, and storage means for storing the correspondence value for each charge, and the charging device obtains the correspondence value, and condition setting for setting the charging condition based on the correspondence value And a charging control means for controlling charging of the secondary battery using the charging condition.

  According to such a configuration, the charging condition can be set based on the corresponding value that is an index indicating the degree of deterioration of the secondary battery. For this reason, according to the deterioration degree of a secondary battery, the charge conditions which reduce the burden at the time of charge of a secondary battery can be set, and the lifetime of a secondary battery can be made long life. Moreover, since the condition setting means automatically sets the charging condition, it is possible to reduce the user's trouble.

  In the above configuration, the corresponding value calculating means includes a charging current detecting means for detecting a charging current when the secondary battery is charged, and a clock means for measuring a charging time when the secondary battery is charged. It is preferable that the apparatus includes a calculation unit that calculates the corresponding value from the charging current detected by the charging current detection unit and the charging time measured by the clock unit.

  According to such a configuration, a corresponding value corresponding to the charge capacity supplemented to the secondary battery can be calculated with a simple configuration from the charging current and the charging time.

  Further, it is preferable that the charging condition includes a charging target voltage value of the secondary battery, and the condition setting means sets the charging target voltage value based on the corresponding value.

  According to such a configuration, it is possible to set a charging target voltage value that reduces the burden at the time of charging the secondary battery according to the degree of deterioration of the secondary battery, so that the life of the secondary battery can be made long. it can.

  The charge control means selectively performs constant current charge control for charging the secondary battery with a constant current value and constant voltage charge control for charging the secondary battery with a constant voltage value, Preferably, the charging condition includes a constant current value in the constant current charging control, and the condition setting unit sets the constant current value based on the corresponding value.

  According to such a configuration, it is possible to set a constant current value that reduces the burden at the time of charging the secondary battery according to the degree of deterioration of the secondary battery, and thus the life of the secondary battery can be made long. .

  The charge control means selectively performs constant current charge control for charging the secondary battery with a constant current value and constant voltage charge control for charging the secondary battery with a constant voltage value, The charging is terminated when the charging current becomes equal to or lower than the termination current value in the constant voltage charging control, the charging condition includes the termination current value in the constant voltage charging control, and the condition setting means is based on the corresponding value. It is preferable to set the end current value.

  According to such a configuration, the end current value for reducing the burden at the time of charging the secondary battery can be set according to the degree of deterioration of the secondary battery, so the life of the secondary battery can be extended. .

  Further, it is preferable that the condition setting means sets the charging condition based on an integrated corresponding value that is a value obtained by integrating a plurality of the corresponding values.

  According to such a configuration, since the integrated corresponding value that is a value obtained by integrating a plurality of corresponding values is used as a value indicating the degree of deterioration of the secondary battery, the total amount of charge capacity replenished to the secondary battery is grasped. Can do. This makes it easy to determine the degree of deterioration.

  Moreover, it is preferable that the condition setting means sets the charging condition based on the previous corresponding value stored when the previous charging was performed.

  According to such a configuration, since the corresponding value stored at the previous charge is used as the value indicating the degree of deterioration of the secondary battery, the charge capacity replenished to the latest secondary battery can be grasped. This makes it easy to determine the degree of deterioration.

  Further, the condition setting means sets the charging condition based on an integrated corresponding value that is a value obtained by integrating a plurality of the corresponding values, and when the integrated corresponding value is less than a predetermined value, the charging target voltage When the value is set to the first voltage value and the integration corresponding value is equal to or greater than the predetermined value, the charging target voltage value may be set to a second voltage value lower than the first voltage value. preferable.

  According to such a configuration, a charging target voltage value lower than a charging target voltage value set for a secondary battery with a low degree of deterioration can be set for a secondary battery with a large integrated correspondence value and a high degree of deterioration. Further, it is possible to realize charging with reduced burden at the time of charging the secondary battery, and to extend the life of the secondary battery.

  Further, the condition setting means sets the charging condition based on the previous corresponding value stored at the time of previous charging, and if the previous corresponding value is equal to or greater than a predetermined value, the charging target voltage value is When the voltage value is set to 1 and the previous corresponding value is less than a predetermined value, it is preferable to set the charging target voltage value to a second voltage value lower than the first voltage value.

  According to such a configuration, a charging target voltage value lower than a charging target voltage value set for a secondary battery with a low deterioration degree can be set for a secondary battery with a small previous correspondence value and a high deterioration degree. Further, it is possible to realize charging with reduced burden at the time of charging the secondary battery, and to extend the life of the secondary battery.

  The condition setting means sets the charging condition based on an integrated corresponding value that is a value obtained by integrating a plurality of the corresponding values, and when the integrated corresponding value is less than a predetermined value, the constant current value Is set to the first current value, and the constant current value is preferably set to a second current value smaller than the first current value when the integrated corresponding value is equal to or greater than a predetermined value.

  According to such a configuration, a constant current value lower than a constant current value set for a secondary battery with a low degree of deterioration can be set for a secondary battery with a large integrated correspondence value and a high degree of deterioration. Charging with reduced burden during charging of the secondary battery can be realized, and the life of the secondary battery can be extended.

  Further, the condition setting means sets the charging condition based on the previous corresponding value stored at the time of the previous charging, and when the previous corresponding value is equal to or greater than a predetermined value, the constant current value is set to the first current value. If the previous corresponding value is less than a predetermined value, the constant current value is preferably set to a second current value smaller than the first current value.

  According to such a configuration, a constant current value lower than a constant current value set for a secondary battery with a low degree of deterioration can be set for a secondary battery with a small previous correspondence value and a high degree of deterioration. Charging with reduced burden during charging of the secondary battery can be realized, and the life of the secondary battery can be extended.

  The condition setting means sets the charging condition based on an integrated corresponding value that is a value obtained by integrating a plurality of the corresponding values. When the integrated corresponding value is less than a predetermined value, the end current value Is set to a third current value, and when the integrated corresponding value is equal to or greater than a predetermined value, it is preferable to set the end current value to a fourth current value larger than the third current value.

  According to such a configuration, since a final current value larger than a final current value set for a secondary battery with a low degree of degradation can be set for a secondary battery with a large integrated correspondence value and a high degree of degradation, Charging with reduced burden during charging of the secondary battery can be realized, and the life of the secondary battery can be extended.

  Further, the condition setting means sets the charging condition based on the previous corresponding value stored at the time of the previous charging, and when the previous corresponding value is equal to or greater than a predetermined value, the condition current setting means sets the end current value to the third value. If the previous corresponding value is less than a predetermined value, the end current value is preferably set to a fourth current value that is larger than the third current value.

  According to such a configuration, it is possible to set a final current value larger than a final current value set for a secondary battery having a low degree of deterioration with respect to a secondary battery having a small previous correspondence value and a high degree of deterioration. Charging with reduced burden during charging of the secondary battery can be realized, and the life of the secondary battery can be extended.

  The present invention further provides a charging device for charging a secondary battery housed in a battery pack, wherein the charging control value is changed according to the past charging capacity of the secondary battery. provide.

  According to such a configuration, the charge control value can be changed according to the past charge capacity serving as an index indicating the degree of deterioration of the secondary battery. For this reason, according to the deterioration degree of a secondary battery, the charge control value which reduces the burden at the time of charge of a secondary battery can be set, and the lifetime of a secondary battery can be made long life.

  In the above configuration, the charge capacity is preferably the charge capacity at the previous charge.

  The charge capacity is preferably an accumulated charge capacity charged in the past.

  The charge control value is preferably at least one of a charge voltage value, a charge current value, and a termination current value.

  According to the charging device of the present invention, the deterioration of the secondary battery can be suppressed and the life can be extended by reducing the burden at the time of charging the secondary battery.

1 is a circuit diagram including a block diagram of a charging device according to a first embodiment of the present invention. It is a part of flowchart showing charge control in the case of charging a secondary battery using the charging device concerning the 1st Embodiment of this invention. It is a part of flowchart showing charge control in the case of charging a secondary battery using the charging device concerning the 1st Embodiment of this invention. It is a figure which shows the deterioration degree of the secondary battery in the charging cycle of the secondary battery by the charging device concerning the 1st Embodiment of this invention. It is a part of flowchart which shows charge control in the case of charging a secondary battery using the charging device concerning the 2nd Embodiment of this invention. It is a part of flowchart which shows charge control in the case of charging a secondary battery using the charging device concerning the 2nd Embodiment of this invention. It is a part of flowchart which shows charge control in the case of charging a secondary battery using the charging device concerning the 3rd Embodiment of this invention. It is a part of flowchart which shows charge control in the case of charging a secondary battery using the charging device concerning the 3rd Embodiment of this invention. It is a figure which shows the deterioration degree of the secondary battery in the charging cycle of the secondary battery by the charging device concerning the 3rd Embodiment of this invention. It is a part of flowchart which shows charge control in the case of charging a secondary battery using the charging device concerning the 4th Embodiment of this invention. It is a part of flowchart which shows charge control in the case of charging a secondary battery using the charging device concerning the 4th Embodiment of this invention. It is a part of flowchart showing charge control in the case of charging a secondary battery using the charging device concerning the 5th Embodiment of this invention. It is a part of flowchart showing charge control in the case of charging a secondary battery using the charging device concerning the 5th Embodiment of this invention. It is a figure which shows the deterioration degree of the secondary battery in the charging cycle of the secondary battery by the charging device concerning the 5th Embodiment of this invention. It is a part of flowchart which shows charge control in the case of charging a secondary battery using the charging device concerning the 6th Embodiment of this invention. It is a part of flowchart which shows charge control in the case of charging a secondary battery using the charging device concerning the 6th Embodiment of this invention.

  A charging apparatus 1 according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a circuit diagram including a block diagram illustrating a configuration of a circuit inside charging device 1 and a circuit inside battery pack 2 attached to charging device 1 according to the present embodiment.

  First, the battery pack 2 to be charged will be described. As shown in FIG. 1, the battery pack 2 includes a battery set 2A, a protection IC 2b, a power supply circuit 2c, a memory 2e, a battery-side microcomputer 2d, and a shunt resistor 2g.

  The battery set 2A has a configuration in which four battery cells 2a are connected in series. The battery cell 2a is, for example, a lithium ion battery with a rated voltage of 3.6V. The protection IC 2b monitors the voltage of each battery cell 2a, and outputs an abnormal signal to the battery-side microcomputer 2d when any one of them becomes an abnormal state due to overcharge or overdischarge. The power supply circuit 2c transforms the voltages of the plurality of battery cells 2a and supplies the power to the battery-side microcomputer 2d. The shunt resistor 2g is connected in series with the battery set 2A and is used to detect a current flowing through the battery cell 2a. The shunt resistor 2g corresponds to charging current detection means.

  The battery-side microcomputer 2d includes a RAM, a ROM, a timer function, an arithmetic function, and the like, and is connected to the protection IC 2b, the power supply circuit 2c, the memory 2e, and the shunt resistor 2g. Moreover, the battery side microcomputer 2d is provided with the information communication port 2f, and mutually communicates various information with the charging device 1 via the information communication port 2f. When an abnormal signal is input from the protection IC 2b to the battery-side microcomputer 2d, the battery-side microcomputer 2d outputs a charging abnormality stop signal to the charging device 1 via the information communication port 2f.

  When a charging start signal indicating that charging of the battery cell 2a is started via the information communication port 2f is input from the charging device 1 to the battery side microcomputer 2d, the battery side microcomputer 2d operates the timer function to make a fixed time interval. The operation of detecting the charging current using the shunt resistor 2g and storing the detected charging current value (charging current value) in the RAM is repeated at regular intervals. When a charging end signal indicating that charging of the battery cell 2a has been completed is input or when the battery pack 2 is detached from the charging device 1, the battery-side microcomputer 2d stops the operation and saves it in the RAM. The product of the sum of all the charging current values and the certain time is calculated, and the calculation result is stored as a corresponding value in the memory 2e. The detection of the charging current is calculated by taking in the voltage drop value of the shunt resistor 2g by the battery side microcomputer 2d. The shunt resistor 2g and the battery side microcomputer 2d correspond to corresponding value calculation means. The battery side microcomputer 2d corresponds to a clock unit and a calculation unit.

  The memory 2e stores a corresponding value for each charge calculated by the battery-side microcomputer 2d. The corresponding value is an integral value related to the time of the charging current from the start of charging to the end (stop) of charging, and is a value corresponding to the charging capacity replenished to the battery cell 2a by charging. The corresponding value is information that is used by the charging-side microcomputer 50 described later to determine the degree of deterioration of the battery cell 2a during charging. Further, among the corresponding values, a previous corresponding value that is a corresponding value calculated at the time of previous charging, or an integrated corresponding value that is an integration of a plurality of corresponding values up to the previous charging time, and the like are used as a reference for determining the deterioration degree of the battery cell 2a. can do. The memory 2e corresponds to storage means.

  In general, as the secondary battery deteriorates, the discharge capacity decreases. As the discharge capacity decreases, the capacity that can be charged (replenished charge capacity) also decreases. The corresponding value when charging is small. Therefore, when the previous corresponding value is used as a criterion for determining the deterioration of the battery cell 2a, if the previous corresponding value is equal to or greater than the predetermined value, the deterioration degree of the battery cell 2a is determined to be low, and if the previous corresponding value is less than the predetermined value, the deterioration is determined. The degree is determined to be high. In addition, it is desirable that the value corresponding to the previous time (the charge capacity at the time of the previous charge) is the charge capacity when the battery is fully charged at the time of the previous charge. When the battery is fully charged, a full charge signal may be transmitted from the information port 53 of the charge side microcomputer 50 to the information communication port 2f of the battery side microcomputer 2d, and the information may be stored in the memory 2e. When the previous charge is not fully charged, the corresponding value (charge capacity) when the battery is fully charged before or twice before is sufficient. It may be possible to remove the battery pack 2 from the charging device 1 in the middle of charging. In this case (the battery is not fully charged), it cannot be calculated how much the charging capacity is at full charge. It is difficult to determine the degree of deterioration at the next charge from the capacity. Similarly, in the case of the accumulated capacity due to past charging as described later, the capacity when charging is stopped during charging may not be accumulated. You may consider (integrate).

  In general, it is known that the rechargeable battery is charged more frequently and the more the replenished charge capacity is, the more the deterioration proceeds, and the integration of corresponding values stored for each charge, that is, the integrated corresponding value is large. As the number of times of charging and the charged capacity are increased, it can be determined that the deterioration is progressing. Therefore, when the integrated correspondence value is used as a criterion for determining the deterioration of the battery cell 2a, if the integrated correspondence value is equal to or greater than the predetermined value, the deterioration degree of the battery cell 2a is determined to be high. The degree is determined to be low.

  The memory 2e stores the rated voltage and rated capacity of the battery cell 2a, the number of cells of the battery set 2A (number of battery cells 2a), and the like as battery voltage type information. In addition, you may memorize | store these battery voltage seed | species information in ROM incorporated in the battery side microcomputer 2d instead of the memory 2e.

  Next, the charging device 1 will be described. The charging device 1 includes a first rectifying / smoothing circuit 10, a switching circuit 20, a second rectifying / smoothing circuit 30, an auxiliary power circuit 40, a charging side microcomputer 50, a charging current control circuit 60, and a charging current setting circuit 70. The battery voltage detection circuit 80, the display circuit 90, the charge voltage control circuit 100, the charge control signal transmission units 4 and 5, and the switching power supply circuit 6, and the battery pack 2 is mounted. In this state, the battery cell 2a in the battery pack 2 is charged by constant current / constant voltage charging control. The constant current / constant voltage charging control means that when charging is started, charging is performed while controlling the charging current to a constant current value (constant current value) (constant current control section), and the voltage of the entire battery set 2A is predetermined. After reaching the voltage, charging is performed while keeping the charging voltage at the predetermined voltage (constant voltage control section), and charging is terminated when the charging current falls below a predetermined end current value in the constant voltage control section. is there.

  The first rectifying / smoothing circuit 10 includes a full-wave rectifying circuit 11 and a smoothing capacitor 12. The full-wave rectifying circuit 11 performs full-wave rectification on the AC voltage supplied from the AC power supply 7, and the smoothing capacitor 12. Smoothes and outputs a DC voltage. The AC power source 7 is an external power source such as a commercial power source.

  The switching circuit 20 is connected to the output side of the first rectifying / smoothing circuit 10, and includes a high-frequency transformer 21, a MOSFET 22, and a PWM control IC 23. The PWM control IC 23 changes the drive pulse width of the MOSFET 22, the MOSFET 22 performs switching according to the drive pulse width, and the DC output from the first rectifying and smoothing circuit 10 is used as the voltage of the pulse train waveform. The voltage of the pulse train waveform is applied to the primary winding of the high frequency transformer 21, and is stepped down (or boosted) by the high frequency transformer 21 and output to the second rectifying and smoothing circuit 30.

  The second rectifying / smoothing circuit 30 includes a diode 31, a smoothing capacitor 32, and a discharging resistor 33. The second rectifying / smoothing circuit 30 rectifies and smoothes the output voltage obtained from the secondary winding of the high-frequency transformer 21 to generate a DC voltage. The DC voltage is generated and output from the positive terminal 1 a and the negative terminal 1 b of the charging device 1.

  The auxiliary power supply circuit 40 is connected to the output side of the first rectifying and smoothing circuit 10, and is a constant voltage for supplying a stabilized reference voltage Vcc to various circuits such as the charging side microcomputer 50 and operational amplifiers 61 and 65 described later. It is a power supply circuit. The auxiliary power supply circuit 40 is mainly composed of coils 41a, 41b and 41c, a switching element 42, a control element 43, a rectifier diode 44, a three-terminal regulator 46, oscillation prevention capacitors 45 and 47, and a reset IC 48. It is configured. The reset IC 48 is an IC that outputs a reset signal to the charging side microcomputer 50 and resets the charging side microcomputer 50.

  The switching power supply circuit 6 is a rectifying / smoothing circuit connected to the auxiliary power supply circuit 40, the switching circuit 20 and the like and serving as a power supply for the PWM control IC 23. The switching power supply circuit 6 is mainly composed of a coil 6a, a rectifying diode 6b, and a smoothing capacitor 6c. ing.

  The charging side microcomputer 50 mainly includes a first output unit 51a, a second output unit 51b, an A / D input port 52, an information port 53, a reset port 54, a ROM, a RAM, and an arithmetic unit. It is configured. The charging-side microcomputer 50 processes various signals input to the A / D input port 52 and the information port 53, and outputs various signals based on the results from the first output unit 51a and the second output unit 51b to the charging current setting circuit 70. , And output to the display circuit 90, the charging voltage control circuit 100, etc., to control the operation of the charging device 1.

  The first output unit 51 a has a plurality of ports, and each is connected to the display circuit 90 and the charge control signal transmission unit 4. The second output unit 51 b has a plurality of ports, and each is connected to the charging current setting circuit 70 and the charging voltage control circuit 100.

  The A / D input port 52 has a plurality of ports, and each is connected to the charging current control circuit 60 and the battery voltage detection circuit 80. The information port 53 is connected to the information communication port 2 f of the battery pack 2, and the reset port 54 is connected to the auxiliary power circuit 40.

  Further, the ROM stores three types of termination current values Ia, Ib, and Ic that are used as threshold values when charging is terminated in the constant current / constant voltage charging control. Ia, Ib, and Ic have a relationship of Ia <Ib <Ic, and when the battery cell 2a is charged, one of the three types can be selectively set as the end current value. In general, when the termination current value is low, the secondary battery is charged to a value close to the maximum capacity, which places a heavy burden on the secondary battery. On the other hand, when the termination current value is high, charging is shallower than when charging up to near the maximum capacity of the secondary battery, and the burden when charging the secondary battery is small. Note that different values may be stored for the termination current values Ia, Ib, and Ic depending on the type of battery pack 2 (rated voltage, number of cells, etc.). That is, if the type of the battery pack 2 is different, the combination of the constant current values Ia, Ib, and Ic may be different.

  The charging current setting circuit 70 is a circuit for setting a constant current value, and includes resistors 71, 72, 73 and 74. The resistors 71 and 72 are connected in series between the reference voltage Vcc and the ground, and a connection point between the resistors 71 and 72 is connected to the charging current control circuit 60. One end of each of the resistors 73 and 74 is connected to a connection point between the resistor 71 and the resistor 72, and the other end is individually connected to a corresponding port of the second output unit 51b.

  In the present embodiment, the charging current setting circuit 70 can selectively set three types of current values I1, I2, and I3 as constant current values during charging. Here, I1, I2, and I3 satisfy the relationship of I1> I2> I3. Specifically, no signal is output from the ports connected to the resistors 73 and 74 of the second output unit 51b, and the value obtained by dividing the reference voltage Vcc by the resistors 71 and 72 is a constant current value. This is a reference value for setting as I1. In the present embodiment, the constant current value I1 is 7.5 A as an example.

  Further, the port connected to the resistor 73 in the second output unit 51b outputs a low signal, and the port connected to the resistor 74 in the second output unit 51b does not output a signal, so that the reference voltage Vcc is The voltage is divided by the combined resistance of the resistors 72 and 73 and the resistor 71, and the divided value becomes a reference value for setting the constant current value as I2. The constant current value I2 is smaller than the constant current value I1, and in the present embodiment, the constant current value I2 is 5.0 A as an example.

  Further, by outputting no signal from the port connected to the resistor 73 in the second output unit 51 b and outputting a low signal from the port connected to the resistor 74, the reference voltage Vcc becomes the resistance of the resistors 72 and 74. The voltage is divided by the combined resistance and the resistance 71, and the divided value becomes a reference value for setting the constant current value as I3. The constant current value I3 is smaller than the constant current value I2, and in the present embodiment, the constant current value I3 is 3.5 A as an example.

  The constant current values I1, I2, and I3 may be set to different values depending on the type of battery pack 2 (rated voltage, number of cells, etc.). That is, if the type of the battery pack 2 is different, the combinations of the constant current values I1, I2, and I3 may be different.

  The charging current control circuit 60 is connected to the charging current setting circuit 70 and the like, and controls the charging current based on the value set by the charging current setting circuit 70. The charging current control circuit 60 includes operational amplifiers 61 and 65, resistors 62, 63, 64, 66 and 67, and a diode 68. The output side of the operational amplifier 61 is connected to the A / D input port 52.

  The current detection resistor 3 is connected between the second rectifying / smoothing circuit 30 and the charging voltage control circuit 100 and detects a charging current flowing through the battery pack 2.

  The battery voltage detection circuit 80 is a circuit that detects the battery voltage, and includes resistors 81 and 82. The resistors 81 and 82 are connected in series between the plus terminal 1a of the charging device 1 and the ground, and the connection point between the resistors 81 and 82 is connected to the A / D input port 52 of the charging side microcomputer 50. Yes. The voltage supplied to the battery pack 2, that is, the voltage of the battery pack 2 is divided by the resistors 81 and 82, and the value is input to one of the A / D input ports 52 of the charging side microcomputer 50 as battery voltage information. When power is not supplied to the battery pack 2, information indicating the voltage of the battery pack 2 is input as battery voltage information to one of the A / D input ports 52 via the battery voltage detection circuit 80. The

  The charge control signal transmission unit 4 includes a photocoupler 4a and an FET 4b. The photocoupler 4a is connected between the switching circuit 20 and the switching power supply circuit 6, and transmits a signal for controlling the start / stop of the PWM control IC 23. The FET 4b is connected between the light emitting element constituting the photocoupler and the ground, and the gate of the FET 4b is connected to the first output unit 51a. When the port connected to the FET 4b in the first output unit 51a of the charging side microcomputer 50 outputs a high signal, the FET 4b is turned on and the photocoupler of the charge control signal transmission unit 4 is turned on. As a result, the PWM control IC 23 is activated and charging is started. Further, when a port connected to the FET 4b in the first output unit 51a outputs a low signal, the FET 4b is turned off, and the photocoupler of the charge control signal transmission unit 4 is turned off. As a result, the PWM control IC 23 stops and charging stops (ends).

  The charging current signal transmission unit 5 includes a photocoupler or the like, and feeds back the charging voltage and charging current signals from the charging voltage control circuit 100 and the charging current control circuit 60 to the PWM control IC 23.

  The display circuit 90 is a circuit for displaying the state of charge, and includes an LED 91 and resistors 92 and 93. When the port connected to the resistor 92 in the first output unit 51a outputs a high signal, the LED 91 lights red, and when the port connected to the resistor 93 in the first output unit 51a outputs a high signal, the LED 131 is turned on. Lights up green, and when a high signal is output from both ports, the LED 91 lights up orange. In the present embodiment, the charging-side microcomputer 50 turns on the red LED 91 in a state before charging when the battery pack 2 is not connected or in a standby state for charging, and turns on orange by simultaneously lighting two LEDs 91 during charging. The LED 91 is lit in green after the end of charging.

  The charging voltage control circuit 100 is connected to the second rectifying / smoothing circuit 30 and controls the charging voltage. The charging voltage control circuit 100 includes resistors 101, 103, 105, 106, 107, 108, 110, 111, 112, 114, 115, 116, 118, 121, 122, 123, 125, 126, 127, potentiometer 102, and FET 109. , 113, 117, 124, 128, capacitor 104, shunt regulator 120, rectifier diode 119, and the like. Resistors 108, 112, 116, 123, 127 are connected to each of the plurality of ports of the second output unit 51b.

  The charging voltage is set by switching on / off the FETs 109, 113, 117, 124, and 128 according to a signal from the second output unit 51 b of the charging side microcomputer 50. In the following description, the combined resistance determined by the resistors 101, 121, 125 and the potentiometer 102 is R1, and the combined resistance determined by the resistors 105, 106, 110, 114 is R2.

  That is, the combined resistance R1 changes depending on whether the FETs 124 and 128 are turned on or off. When each of the FETs 124 and 128 is off, the combined resistance R1 is a series resistance of the resistance 101 and the potentiometer 102. When the FET 124 is on and the FET 128 is off, the resistance R1 is a series resistance of the combined resistance of the resistance 101 and the resistance 121 and the potentiometer 102. When the FET 124 is off and the FET 128 is on, the resistor R1 is a series resistance of the combined resistance of the resistor 101 and the resistor 125 and the potentiometer 102.

  The resistance R2 is changed by turning on / off the FETs 109, 113, and 117, and is a combined resistance of the resistance 105 and the resistance of the resistances 106, 110, and 114 in which the corresponding FETs 109, 113, and 117 are turned on.

  The charging voltage increases substantially in proportion to the resistor R1, and increases in proportion to the reciprocal of the resistor R2. In the present embodiment, the charging side microcomputer 50 switches the charging voltage by switching on / off of the FETs 109, 113, 117, 124, and 128.

  The charging-side microcomputer 50 determines the charging voltage based on the type (rated voltage, number of cells, etc.) of the battery pack 2 that is attached and the corresponding value. In the present embodiment, a charge target voltage value is set for each type of battery pack 2. Specifically, the charging voltage of the entire battery set 2A (hereinafter, battery set charging voltage value) is set. In the present embodiment, any one of the three voltage values V1, V2, and V3 is set as the battery assembly charging voltage value (charging target voltage value). Here, in the same type of battery cell 2a, the voltage values V1, V2, and V3 are constant voltage values, and have a relationship of V1> V2> V3. As the voltage value V1, the maximum charging voltage of the battery pack 2 (battery set 2A) is set. When the rated voltage of the battery cell 2a is 3.6V, for example, when the charge target voltage value is set to V1, V1 is set to 4.2V / cell × cell number, and the charge target voltage value is set to V2. In this case, V2 is 4.15V / cell × cell number, and V3 is 4.10V / cell × cell number when the charging target voltage value is set to V3.

  Specifically, when the high signal is not output from the second output unit 51b of the charge side microcomputer 50 and the FET 124 and FET 128 are kept in the OFF state, the charge target voltage value is set to V1. Further, when a high signal is output from the port of the second output unit 51b connected to the gate of the FET 124 via the resistor 123 to turn on the FET 124, the charge target voltage value is set to V2. Further, when a high signal is output from the port of the second output unit 51b connected to the gate of the FET 128 via the resistor 127 to turn on the FET 128, the charge target voltage value is set to V3. Further, the charging target voltage value is set based on the above-described corresponding value, and when it is determined from the corresponding value that the degree of deterioration of the battery cell 2a is high, it is the lowest voltage value among the three types of voltage values. When V3 is set and the degree of deterioration is determined to be medium, it is set to V2 which is a medium voltage value among the three types of voltage values, and when it is determined that the degree of deterioration is low, the maximum The charging voltage is set to V1.

  The on / off switching of the FETs 109, 113, 117 of the charging voltage control circuit 100 corresponds to the number of battery cells 2a. When the number of battery cells 2a is two, the FET 109, All FETs 113 and 117 are turned off. When the number of battery cells 2a is three, a high signal is output from the port of the second output unit 51b connected to the gate of the FET 109 via the resistor 108 to turn on the FET 109. Similarly, the FET 113 is turned on when the number of the battery cells 2a is 4, and the FET 117 is turned on when the number is 5 cells.

  Thus, the on / off switching of the FETs 124 and 128 corresponds to the setting of the charging target voltage value, and the on / off switching of the FETs 109, 113, and 117 is the number of battery cells 2a constituting the battery set 2A. It corresponds to. For example, when charging a battery set having three battery cells 2a at the charge target voltage value V2, the charge target voltage value (battery set charge voltage value) is 4.15 V / cell by turning on the FET 124 and the FET 109. × When charging a battery set having 5 battery cells 2a at the charge target voltage value V3 set to a voltage value corresponding to 3 cells, the charging target voltage value (battery set charging) is set by turning on FET 128 and FET 117. The voltage value is set to a voltage value corresponding to 4.10 V / cell × 5 cells. The charging voltage control circuit 100, the charging current setting circuit 70, and the charging side microcomputer 50 correspond to condition setting means.

  Next, the charging control of the charging device 1 according to the first embodiment of the present invention will be described with reference to the flowcharts of FIGS. In the charging device 1 according to the present embodiment, the degree of deterioration of the battery cell 2a is determined using the previous corresponding value that is the corresponding value stored when the battery pack 2 was previously charged, and charging is performed according to the degree of deterioration. Constant current constant voltage charge control is performed by setting a target voltage value (Vc).

  When charging the battery cell 2a whose deterioration has progressed and the discharge capacity is reduced, the charging target voltage value (Vc) is set to the maximum charging voltage V1, and if the charging is attempted to the maximum charging voltage, the burden on the battery cell 2a In the charging apparatus 1 according to the present embodiment, the charging target voltage value (Vc) is set according to the degree of deterioration from the three voltage values V1, V2, and V3. By setting this value, the burden on the battery cell 2a is reduced and a long life is realized.

  First, when the AC power supply 7 and the charging device 1 are connected, the charging-side microcomputer 50 starts operating (S201), and the display circuit 90 is lit red to indicate that it is in a charging standby state before charging (S202). . In order to light the display circuit 90 in red, a high signal is output from the port connected to the resistor 92 in the first output unit 51a, and the LED 91 is lit in red.

  Next, it is determined whether or not the battery pack 2 is mounted on the charging device 1 (S203). Whether or not the battery pack 2 is mounted is determined by communication between the battery side microcomputer 2d and the charging side microcomputer 50 via the information communication port 2f. If the battery pack 2 is not mounted on the charging device 1 in step 203, step 202 and step 203 are repeated until the battery pack 2 is mounted on the charging device 1, and the charging standby state is continued. On the other hand, when the battery pack 2 is mounted on the charging device 1, the battery voltage type (number of cells, etc.) is detected (S204). In step 204, the charging side microcomputer 50 detects battery voltage type information stored in the memory 2e of the battery pack 2 by communicating with the battery side microcomputer 2d via the information communication port 2f.

  When the charging side microcomputer 50 detects the battery voltage type information, the charging side microcomputer 50 sets a charging condition according to the number of cells based on the battery voltage type information (S205). Specifically, since the battery pack 2 mounted on the charging device 1 according to the present embodiment has four cells, the second output unit 51b connected to the gate of the FET 113 via the resistor 112. A high signal is output from the port No. 1 to turn on the FET 113.

  Next, the charging side microcomputer 50 acquires the corresponding value stored in the memory 2e of the battery pack 2 by communicating with the battery side microcomputer 2d via the information communication port 2f. Here, the charging-side microcomputer 50 uses the previous corresponding value (corresponding value stored when the battery pack 2 was previously charged) among the acquired corresponding values to determine the degree of deterioration, and the previous corresponding value is less than the predetermined value a. It is determined whether or not (S206). The ROM of the charge side microcomputer 50 stores in advance predetermined values a and b (a> b) for determining the degree of deterioration of the battery cell 2a. The charging side microcomputer 50 corresponds to an acquisition unit.

  In step 206, when the previous corresponding value is not less than the predetermined value a (degradation degree: low), the charging target voltage value Vc is set to V1 (S207). In order to set the charging target voltage value Vc to V1, the FET 124 and the FET 128 are turned off without outputting a high signal from the second output unit 51b of the charging side microcomputer 50. On the other hand, if the previous corresponding value is less than the predetermined value a, it is further determined whether or not the previous corresponding value is less than the predetermined value b (S208).

  In step 208, when the previous corresponding value is not less than the predetermined value b (deterioration degree: medium), the charging target voltage value Vc is set to V2 (S209). In order to set the charging target voltage value Vc to V2, a high signal is output from the port of the second output unit 51b connected to the gate of the FET 124 via the resistor 123 to turn on the FET 124. On the other hand, when the previous corresponding value is less than the predetermined value b (deterioration degree: high), the charging target voltage value Vc is set to V3 (S210). In order to set the charging target voltage value Vc to V3, a high signal is output from the port of the second output unit 51b connected to the gate of the FET 128 via the resistor 127 to turn on the FET 128.

  As described above, steps 205 to 210 are steps for setting the charging target voltage value Vc. In this embodiment, for example, when the number of cells is 4 and the charging target voltage value Vc is set to V2. The FET 113 and the FET 124 are turned on, and the charge target voltage value Vc is 4 × 4.15V.

  After the charging target voltage value Vc is set, the constant current value Is is set to I1 (S211). The constant current value Is can be set to I1 by not outputting signals from the ports connected to the resistors 73 and 74 in the second output unit 51b of the charging side microcomputer 50, respectively.

  After the constant current value Is is set, the end current value Ie is set to Ia (S212).

  After the charging target voltage value Vc, the constant current value Is, and the end current value Ie are determined, charging of the battery pack 2 is started (S213). To start charging the battery cell 2a, a high signal is output from the port connected to the FET 4b in the first output unit 51a of the charging side microcomputer 50, and the PWM control IC 23 is activated. At the same time as charging is started, a charging start signal is output to the battery pack 2 via the information communication port 2f. When the charging start signal is input, the battery pack 2 starts the above-described operation in order to calculate a corresponding value used for determining the degree of deterioration after the next charging. Further, when charging is started, the display circuit 90 is lit in orange to indicate that charging is in progress (S214). In order to light the display circuit 90 in orange, the LED 91 is lit in orange by outputting a high signal from the port connected to the resistor 92 and the port connected to the resistor 93 in the first output unit 51a.

  The battery cell 2a is first charged with a constant current value Is (Is = I1) that is a constant current value (constant current control section), and then the voltage of the battery set 2A reaches the set charge target voltage value Vc. Then, charging is continued while keeping the charging voltage at the voltage (constant voltage control section). In the constant voltage control section, it is determined whether or not the charging current has become equal to or less than the end current value Ie (Ie = Ia) (S215). If it is determined in step 215 that the charging current is not equal to or less than the termination current value Ie, step 215 is repeated until the charging current becomes equal to or less than the termination current value Ie, and charging is continued. If it is determined that the charging current is equal to or less than the termination current value Ie, the charging is terminated (S216). To end the charging, a low signal is output from the port connected to the FET 4b in the first output unit 51a of the charging side microcomputer 50, and the PWM control IC 23 is stopped.

  When the charging is completed, a charging end signal is output to the battery pack 2. When the charge end signal is input, the battery pack 2 calculates a corresponding value and stores it in the memory 2e. The corresponding value is used to determine the degree of deterioration of the battery cell 2a during the next and subsequent charging. When charging is completed, the display circuit 90 is lit in green to indicate that charging is complete (S217). In order to light the display circuit 90 in green, the LED 91 is lit in green by outputting a high signal from the port connected to the resistor 93 in the first output unit 51a.

  After the charging is completed and the display circuit 90 is lit in green, it is determined whether or not the battery pack 2 is detached from the charging device 1 (S218). If the battery pack 2 is not detached from the charging device 1, step 218 is repeated, and the state where the display circuit 90 is lit in green is maintained. On the other hand, when the battery pack 2 is detached from the charging device 1, the process returns to step 202, and the display circuit 90 is lit in red indicating the standby state before charging. Then, steps 202 and 203 are repeated until the battery pack 2 is mounted again, and the charging standby state is continued. In this way, by setting the charging target voltage value Vc according to the previous corresponding value, the burden at the time of charging the battery cell 2a is reduced and the life is extended.

  FIG. 4 is a diagram illustrating the relationship between the discharge capacity of the battery cell 2a and the number of times of charging (number of cycles). When charging is repeated by a conventional charging device, charging is repeated by the charging device 1 according to the present embodiment. It is the figure which compared with the case. The discharge capacity when the battery cell 2a is repeatedly charged by the conventional charging device is represented by a broken line, and the discharge capacity when the battery cell 2a is repeatedly charged by the charging device 1 according to the present embodiment is a solid line. It is represented.

  When the battery cell 2a is repeatedly charged by the conventional charging device, the deterioration proceeds regardless of the degree of deterioration of the battery cell 2a even when the deterioration of the battery cell 2a has progressed to some extent beyond the number of times of charging N1. Since the battery is charged while being set to the same charge target voltage value as in the case where there is no charge, the deterioration of the battery cell 2a is accelerated after the number of times of charging N1. Furthermore, since the battery is charged with the fixed charge target voltage value even when the deterioration has progressed beyond the number of times of charging N2, the deterioration of the battery cell 2a is further accelerated.

  However, when the charging of the battery cell 2a is repeated by the charging device 1 according to the present embodiment, the charging is performed until the corresponding value that is an index indicating the degree of deterioration of the battery cell 2a is less than the predetermined value a in the number of times of charging N1. The target voltage value is charged at V1, but when the corresponding value is less than the predetermined value a, the charging target voltage value is set to V2 (V2 <V1) in order to suppress the deterioration of the battery cell 2a, and the burden on the battery cell 2a is set. Use a reduced charge. For this reason, the discharge capacity of the battery cell 2a charged by the charging device 1 at the number of times of charging N2 (N2> N1) is larger than the discharge capacity of the battery cell 2a charged by the conventional charging device. Further, when the corresponding value becomes less than the predetermined value b at the number of times of charging N3, the charging target voltage value is set to V3 (V3 <V2), and charging is performed with a reduced burden on the battery cell 2a. The number of times of charging can be repeated while suppressing the progress, and a decrease in discharge capacity can be suppressed.

  Next, the charging device 300 according to the second embodiment of the present invention will be described. Since the configuration of the charging device 300, communication with the battery pack 2, information acquisition means, and the like are the same as the configuration of the charging device 1, the flowcharts of FIG. 5 and FIG. The description will be given with reference.

  In the charging device 300 according to the present embodiment, the battery cell using the integrated corresponding value that is an integration of the corresponding values for the number of times of charging from the first charging to the previous charging stored in the memory 2e of the battery pack 2. The deterioration degree of 2a is discriminate | determined, the charge target voltage value (Vc) according to the deterioration degree is set, and constant current constant voltage charge control is performed.

  The control in Steps 301 to 305 is the same as the control in Steps 201 to 205 of the charging apparatus 1 and thus will not be described.

  In step 306, the charging-side microcomputer 50 acquires the corresponding value stored in the memory 2e. Here, the charging-side microcomputer 50 uses an integrated corresponding value, which is an integration of corresponding values stored in the memory 2e from the first charging to the previous charging, to determine the degree of deterioration, and the integrated corresponding value is less than a predetermined value c. It is determined whether or not. The ROM of the charging side microcomputer 50 stores in advance predetermined values c and d (c <d) for determining the degree of deterioration of the battery cell 2a.

  In step 306, when the integrated correspondence value is less than the predetermined value c (deterioration degree: low), the charging target voltage value Vc is set to V1 (S307). On the other hand, if the integrated correspondence value is not less than the predetermined value c, it is further determined whether or not the integrated correspondence value is less than the predetermined value d (S308).

  In step 308, when the integrated correspondence value is less than the predetermined value d (deterioration degree: medium), the charging target voltage value Vc is set to V2 (S309). On the other hand, when the integrated corresponding value is not less than the predetermined value d (deterioration degree: high), the charging target voltage value Vc is set to V3 (S310).

  Since the control in steps 311 to 318 is the same as the control in steps 211 to 218 in the charging apparatus 1 according to the first embodiment of the present invention, the description thereof is omitted.

  Thus, by setting the charging target voltage value Vc in accordance with the integration corresponding value, the burden at the time of charging the battery cell 2a is reduced, and the life is extended.

  Next, a charging device 400 according to a third embodiment of the present invention will be described with reference to FIGS. Since the configuration of the charging device 400, the communication with the battery pack 2, the information acquisition means, etc. are the same as the configuration of the charging device 1, the flowcharts of FIGS. It explains using. In addition, the same code | symbol is used about the same structure.

  In the charging device 400 according to the present embodiment, the degree of deterioration of the battery cell 2a is determined using the previous corresponding value that is the corresponding value stored when the battery pack 2 was previously charged, and a constant value corresponding to the degree of deterioration is determined. Constant current constant voltage charge control is performed by setting a current value (Is).

  When charging the battery cell 2a whose deterioration has progressed and the discharge capacity is reduced, if the constant current value (Is) is charged with the same constant current value (Is) as when the deterioration has not progressed, the amount of heat generated by the battery cell 2a In the charging apparatus 400 according to the present embodiment, the constant current value (Is) is set according to the degree of deterioration from among the three types of current values I1, I2, and I3. By setting the value, the burden on the battery cell 2a is reduced and a long life is realized.

  Since Steps 401 to 405 are the same as Steps 201 to 205 of the charging apparatus 1, description thereof is omitted.

  In step 406, the charging target voltage value Vc is set to V1.

  Next, the charge side microcomputer 50 acquires the corresponding value stored in the memory 2e. Here, the charging-side microcomputer 50 uses the previous corresponding value (corresponding value stored when the battery pack 2 was previously charged) among the acquired corresponding values to determine the degree of deterioration, and the previous corresponding value is less than the predetermined value a. It is determined whether or not (S407). The ROM of the charge side microcomputer 50 stores in advance predetermined values a and b (a> b) for determining the degree of deterioration of the battery cell 2a.

  In step 407, when the previous corresponding value is not less than the predetermined value a (degradation degree: low), the constant current value Is is set to I1 (S408). The constant current value Is can be set to I1 by not outputting signals from the ports connected to the resistors 73 and 74 in the second output unit 51b of the charging side microcomputer 50, respectively. On the other hand, if the previous corresponding value is less than the predetermined value a, it is further determined whether or not the previous corresponding value is less than the predetermined value b (S409).

  In step 409, when the previous correspondence value is not less than the predetermined value b (deterioration degree: medium), the constant current value Is is set to I2 (S410). The port connected to the resistor 73 in the second output unit 51b outputs a low signal, and the port connected to the resistor 74 in the second output unit 51b does not output a signal, whereby the constant current value Is is set to I2. Set. On the other hand, when the previous corresponding value is less than the predetermined value b (degradation degree: high), the constant current value Is is set to I3 (S411). The constant current value Is is set to I3 by outputting no signal from the port connected to the resistor 73 in the second output unit 51b and outputting a low signal from the port connected to the resistor 74.

  After the constant current value Is is set, the end current value Ie is set to Ia (S412).

  After the charging target voltage value Vc, the constant current value Is, and the end current value Ie are determined, charging of the battery pack 2 is started (S313). Further, when charging is started, the display circuit 90 is lit in orange to indicate that charging is in progress (S314).

  The battery cell 2a is first charged with the constant current value Is set in steps 407 to 411 (constant current control section), and then the charge target voltage value Vc (Vc = V1) in which the voltage of the battery set 2A is set. When it reaches, charging continues while keeping the charging voltage at that voltage (constant voltage control section). In the constant voltage control section, it is determined whether or not the charging current has become equal to or less than the end current value Ie (Ie = Ia) (S415). If it is determined in step 415 that the charging current is not equal to or smaller than the termination current value Ie, step 415 is repeated until the charging current becomes equal to or smaller than the termination current value Ie, and charging is continued. If it is determined that the charging current is equal to or less than the termination current value Ie, the charging is terminated (S416). Hereinafter, the control in Steps 417 and 418 is the same as the control in Steps 217 and 218 of the charging device 1, and thus the description thereof is omitted.

  In this way, by setting the constant current value Is according to the previous corresponding value, the burden at the time of charging the battery cell 2a is reduced and the life is extended.

  FIG. 9 is a diagram showing the relationship between the discharge capacity of the battery cell 2a and the number of times of charging (number of cycles). When charging is repeated by the conventional charging device and charging is repeated by the charging device 400 according to the present embodiment. It is the figure which compared with the case. The discharge capacity when the battery cell 2a is repeatedly charged by the conventional charging device is represented by a broken line, and the discharge capacity when the battery cell 2a is repeatedly charged by the charging device 1 according to the present embodiment is a solid line. It is represented.

  When the battery cell 2a is repeatedly charged by the conventional charging device, the deterioration proceeds regardless of the degree of deterioration of the battery cell 2a even when the deterioration of the battery cell 2a has progressed to some extent beyond the number of times of charging N1. Since the battery is charged while being set to the same constant current value as in the case where there is no battery, the deterioration of the battery cell 2a is accelerated after the number of times of charging N1. Furthermore, since the battery is charged with a fixed constant current value even in a state where the deterioration has progressed beyond the number of times of charging N2, the deterioration of the battery cell 2a is further accelerated.

  However, when the charging of the battery cell 2a is repeated by the charging device 400 according to the present embodiment, until the corresponding value, which is an index indicating the degree of deterioration of the battery cell 2a, is less than the predetermined value a in the number of times of charging N1, it is constant. The current value is charged at I1, but when the corresponding value is less than the predetermined value a, the constant current value is set to I2 (I2 <I1) to suppress the deterioration of the battery cell 2a, thereby reducing the burden on the battery cell 2a. Charge the battery. For this reason, the discharge capacity of the battery cell 2a charged by the charging device 400 at the number of times of charging N2 (N2> N1) is larger than the discharge capacity of the battery cell 2a charged by the conventional charging device. Further, when the corresponding value becomes less than the predetermined value b at the number of times of charging N3, the constant current value is set to I3 (I3 <I2), and charging is performed while reducing the burden on the battery cell 2a. The number of times of charging can be repeated while suppressing the decrease in discharge capacity.

  Next, a charging device 500 according to a fourth embodiment of the present invention will be described. Since the configuration of the charging device 500, the communication with the battery pack 2, the information acquisition means, etc. are the same as the configuration of the charging device 1, the flowcharts of FIGS. It explains using. In addition, the same code | symbol is used about the same structure and description is abbreviate | omitted about the same control.

  In charging apparatus 500 according to the present embodiment, a battery cell using an integrated corresponding value that is an integration of corresponding values corresponding to the number of times of charging from the first charging to the previous charging stored in memory 2e of battery pack 2. The deterioration degree of 2a is discriminated, a constant current value (Is) corresponding to the deterioration degree is set, and constant current / constant voltage charging control is performed.

  Since Steps 501 to 505 are the same as Steps 201 to 205 of the charging apparatus 1, description thereof will be omitted.

  In step 506, the charging target voltage value Vc is set to V1.

  In step 507, the charging-side microcomputer 50 acquires the corresponding value stored in the memory 2e. Here, the charging-side microcomputer 50 uses an integrated corresponding value, which is an integration of corresponding values stored in the memory 2e from the first charging to the previous charging, to determine the degree of deterioration, and the integrated corresponding value is less than a predetermined value c. It is determined whether or not. The ROM of the charging side microcomputer 50 stores in advance predetermined values c and d (c <d) for determining the degree of deterioration of the battery cell 2a.

  When the integrated correspondence value is less than the predetermined value c (deterioration degree: low), the constant current value Is is set to I1 (S508). On the other hand, if the integrated correspondence value is not less than the predetermined value c, it is further determined whether or not the integrated correspondence value is less than the predetermined value d (S509).

  In step 509, when the integrated corresponding value is less than the predetermined value d (deterioration degree: medium), the constant current value Is is set to I2 (S510). On the other hand, when the integrated value is not less than the predetermined value d (degradation degree: high), the constant current value Is is set to I3 (S511).

  After the constant current value Is is set, the end current value Ie is set to Ia (S512).

  The battery cell 2a is first charged with the constant current value Is set in steps 507 to 511 (constant current control section), and then the charge target voltage value Vc (Vc = V1) in which the voltage of the battery set 2A is set. When it reaches, charging continues while keeping the charging voltage at that voltage (constant voltage control section). In the constant voltage control section, it is determined whether or not the charging current has become equal to or less than the end current value Ie (Ie = Ia) (S515). If it is determined in step 515 that the charging current is not equal to or less than the termination current value Ie, step 515 is repeated until the charging current is equal to or less than the termination current value Ie, and charging is continued. If it is determined that the charging current is equal to or less than the termination current value Ie, the charging is terminated (S516). Hereinafter, the control in steps 517 and 518 is the same as the control in steps 217 and 218 of the charging apparatus 1, and thus the description thereof is omitted.

  In this way, by setting the constant current value Is according to the integration corresponding value, the burden at the time of charging the battery cell 2a is reduced and the life is extended.

  Next, a charging apparatus 600 according to a fifth embodiment of the present invention will be described with reference to FIGS. Since the configuration of the charging device 600, the communication with the battery pack 2, the information acquisition means, and the like are the same as the configuration of the charging device 1, the flowcharts of FIGS. It explains using. In addition, the same code | symbol is used about the same structure.

  In the charging device 600 according to the present embodiment, the degree of deterioration of the battery cell 2a is determined using the previous corresponding value that is the corresponding value stored when the battery pack 2 was previously charged, and the termination according to the deterioration degree is performed. Constant current constant voltage charging control is performed by setting a current value (Ie).

  When charging the battery cell 2a whose deterioration has progressed and the discharge capacity is reduced, if the end current value (Ie) is charged with the same end current value (Ie) as when the deterioration has not progressed, the maximum capacity of the battery cell 2a In the charging apparatus 600 according to the present embodiment, the final current value (Ie) is set to three types of voltage values Ia, By setting the value according to the degree of deterioration from Ib and Ic, the burden on the battery cell 2a is reduced and a long life is realized.

  Since Steps 601 to 605 are the same as Steps 201 to 205 of the charging apparatus 1, description thereof will be omitted.

  In step 606, the charging target voltage value Vc is set to V1, and in step 607, the constant current value Is is set to I1.

  Next, the charge side microcomputer 50 acquires the corresponding value stored in the memory 2e. Here, the charging-side microcomputer 50 uses the previous corresponding value (corresponding value stored when the battery pack 2 was previously charged) among the acquired corresponding values to determine the degree of deterioration, and the previous corresponding value is less than the predetermined value a. It is determined whether or not (S608). The ROM of the charge side microcomputer 50 stores in advance predetermined values a and b (a> b) for determining the degree of deterioration of the battery cell 2a.

  In step 608, when the previous corresponding value is not less than the predetermined value a (deterioration degree: low), the end current value Ie is set to Ia (S609). On the other hand, if the previous corresponding value is less than the predetermined value a, it is further determined whether or not the previous corresponding value is less than the predetermined value b (S610).

  In step 610, when the previous corresponding value is not less than the predetermined value b (deterioration degree: medium), the end current value Ie is set to Ib (S611). On the other hand, if the previous corresponding value is less than the predetermined value b (degradation degree: high), the end current value Ie is set to Ic (S612).

  After the charging target voltage value Vc, the constant current value Is, and the end current value Ie are determined, charging of the battery pack 2 is started (S613). Furthermore, when charging is started, the display circuit 90 is lit in orange to indicate that charging is in progress (S614).

  The battery cell 2a is first charged with the constant current value Is (Is = I1) set in step 607 (constant current control section), and then the charge target voltage value Vc (Vc) in which the voltage of the battery set 2A is set. = V1), the battery continues to be charged while keeping the charging voltage at that voltage (constant voltage control section). In the constant voltage control section, it is determined whether or not the charging current has become equal to or less than the end current value Ie set in steps 608 to 612 (S615). If it is determined in step 615 that the charging current is not equal to or less than the termination current value Ie, step 615 is repeated until the charging current becomes equal to or less than the termination current value Ie, and charging is continued. If it is determined that the charging current is equal to or less than the termination current value Ie, the charging is terminated (S616). Hereinafter, the control in Steps 617 and 618 is the same as the control in Steps 217 and 218 of the charging apparatus 1, and thus the description thereof is omitted.

  In this way, by setting the end current value Ie according to the previous corresponding value, the burden at the time of charging the battery cell 2a is reduced and the life is extended.

  FIG. 14 is a diagram showing the relationship between the discharge capacity of the battery cell 2a and the number of times of charging (number of cycles). When charging is repeated by the conventional charging device and charging is repeated by the charging device 600 according to the present embodiment. It is the figure which compared with the case. The discharge capacity when the battery cell 2a is repeatedly charged by the conventional charging device is represented by a broken line, and the discharge capacity when the battery cell 2a is repeatedly charged by the charging device 1 according to the present embodiment is a solid line. It is represented.

  When the battery cell 2a is repeatedly charged by the conventional charging device, the deterioration proceeds regardless of the degree of deterioration of the battery cell 2a even when the deterioration of the battery cell 2a has progressed to some extent beyond the number of times of charging N1. Since the battery is charged while being set to the same end current value as in the case where there is no battery, the deterioration of the battery cell 2a is accelerated after the number of times of charging N1. Further, since the battery is charged with the fixed end current value even when the deterioration has progressed beyond the number of times of charging N2, the deterioration of the battery cell 2a is further accelerated.

  However, when the charging of the battery cell 2a is repeated by the charging device 600 according to the present embodiment, the charging is terminated until the corresponding value, which is an index indicating the degree of deterioration of the battery cell 2a, is less than the predetermined value a in the number of times of charging N1. Although the current value is charged with Ia, when the corresponding value is less than the predetermined value a, the termination current value is set to Ib (Ib> Ia) to reduce the load on the battery cell 2a in order to suppress the deterioration of the battery cell 2a. Charge the battery. For this reason, the discharge capacity of the battery cell 2a charged by the charging device 600 at the number of times of charging N2 (N2> N1) is larger than the discharge capacity of the battery cell 2a charged by the conventional charging device. Further, when the corresponding value becomes less than the predetermined value b at the number of times of charging N3, the termination current value is set to Ic (Ic> Ib), and charging is performed while reducing the burden on the battery cell 2a. The number of times of charging can be repeated while suppressing the decrease in discharge capacity.

  Next, a charging device 700 according to a sixth embodiment of the present invention will be described. Since the configuration of the charging device 700, communication with the battery pack 2, information acquisition means, and the like are the same as the configuration of the charging device 1, the control method at the time of charging the different battery cell 2a is shown in the flowcharts of FIGS. It explains using. In addition, the same code | symbol is used about the same structure and description is abbreviate | omitted about the same control.

  In the charging device 700 according to the present embodiment, the battery cell using the integrated corresponding value that is an integration of the corresponding values for the number of times of charging from the first charging to the previous charging stored in the memory 2e of the battery pack 2. The deterioration degree of 2a is discriminated, the end current value (Ie) corresponding to the deterioration degree is set, and constant current / constant voltage charging control is performed.

  The control in Steps 701 to 705 is the same as the control in Steps 201 to 205 of the charging device 1, and thus the description thereof is omitted.

  In step 706, the charging target voltage value Vc is set to V1, and in step 707, the constant current value Is is set to I1.

  In step 708, the charging side microcomputer 50 acquires the corresponding value stored in the memory 2e. Here, the charging-side microcomputer 50 uses an integrated corresponding value, which is an integration of corresponding values stored in the memory 2e from the first charging to the previous charging, to determine the degree of deterioration, and the integrated corresponding value is less than a predetermined value c. It is determined whether or not. The ROM of the charging side microcomputer 50 stores in advance predetermined values c and d (c <d) for determining the degree of deterioration of the battery cell 2a.

  When the integrated correspondence value is less than the predetermined value c (degree of deterioration: low), the end current value Ie is set to Ia (S709). On the other hand, if the integrated correspondence value is not less than the predetermined value c, it is further determined whether or not the integrated correspondence value is less than the predetermined value d (S710).

  In step 710, when the integrated corresponding value is less than the predetermined value d (deterioration degree: medium), the end current value Ie is set to Ib (S711). On the other hand, when the integrated corresponding value is not less than the predetermined value d (deterioration degree: high), the end current value Ie is set to Ic (S712).

  After the charging target voltage value Vc, the constant current value Is, and the end current value Ie are determined, charging of the battery pack 2 is started (S713). Further, when charging is started, the display circuit 90 is lit in orange to indicate that charging is in progress (S714).

  The battery cell 2a is first charged with the constant current value Is (Is = I1) set in step 707 (constant current control section), and then the charge target voltage value Vc (Vc) in which the voltage of the battery set 2A is set. = V1), the battery continues to be charged while keeping the charging voltage at that voltage (constant voltage control section). In the constant voltage control section, it is determined whether or not the charging current has become equal to or less than the end current value Ie set in steps 708 to 712 (S715). If it is determined in step 715 that the charging current is not equal to or less than the termination current value Ie, step 715 is repeated until the charging current is equal to or less than the termination current value Ie, and charging is continued. If it is determined that the charging current is equal to or less than the termination current value Ie, the charging is terminated (S716). Hereinafter, the control in steps 717 and 718 is the same as the control in steps 217 and 218 of the charging apparatus 1, and thus the description thereof is omitted.

  In this way, by setting the end current value Ie according to the integrated value, the burden at the time of charging the battery cell 2a is reduced and the life is extended.

  The charging device according to the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the gist of the invention described in the claims. For example, in the charging device 1, the degree of deterioration of the battery cell 2a is determined using the corresponding value, but the memory 2e is configured to store the number of times of charging, and the degree of deterioration of the battery cell 2a is determined using the number of times of charging. A configuration may be used in which charging conditions such as a charging target voltage value, a constant current value, and a termination current value are set based on the number of times of charging. In this case, since it becomes the structure which estimates the deterioration degree of the battery cell 2a by the frequency | count of charge, it does not necessarily correspond with an actual deterioration degree. Therefore, it is preferable to change the charge control value according to the actual charge capacity.

  Further, Step 211 in the charging control of the charging device 1 may be replaced with Steps 407 to 411 in the charging control of the charging device 400, and the charging target voltage value and the constant current value may be set based on the previous corresponding values.

  Further, step 212 in the charging control of charging device 1 may be replaced with steps 608 to 612 in the charging control of charging device 600, and the charging target voltage value and end current value may be set based on the previous corresponding values.

  Further, step 412 in the charging control of charging device 400 may be replaced with steps 608 to 612 in the charging control of charging device 600, and the constant current value and the end current value may be set based on the previous corresponding values.

  Further, step 211 in the charging control of charging device 1 is replaced with steps 407 to 411 in the charging control of charging device 400, and step 212 is replaced with steps 608 to 612 in the charging control of charging device 600, based on the previous corresponding value. The charging target voltage value, the constant current value, and the end current value may be set.

  Further, step 311 in the charging control of charging device 300 may be replaced with steps 507 to 511 in charging control of charging device 500, and the charging target voltage value and the constant current value may be set based on the integrated correspondence values.

  Further, step 312 in the charging control of charging device 300 may be replaced with steps 708 to 712 in charging control of charging device 700, and the charging target voltage value and the end current value may be set based on the integrated correspondence values.

  Further, Step 512 in the charging control of charging device 500 may be replaced with Steps 708 to 712 in charging control of charging device 700, and the constant current value and the end current value may be set based on the integrated correspondence values.

  Further, step 311 in the charging control of charging device 300 is replaced with steps 507 to 511 in the charging control of charging device 500, and step 312 is replaced with steps 708 to 712 in the charging control of charging device 700, based on the integrated correspondence value. The charging target voltage value, the constant current value, and the end current value may be set.

1,300,400,500,600,700 ... Charging device 2 .... Battery pack 2A ... Battery set 2a ... Battery cell 2d ... Battery side microcomputer 2e ... Memory 2f ... Information communication port 2g ... Shunt Resistance 3 .. Current detection resistance 6 .. Switching power supply circuit 10 .. Rectification smoothing circuit 11 .. Full wave rectification circuit 12 .. Smoothing capacitor 20 .. Switching circuit 30 .. Rectification smoothing circuit 40 .. Auxiliary power supply circuit 50 ..Charging side microcomputer 51a..Output unit 51b..Output unit 52..Input port 53..Information port 60..Charging current control circuit 70..Charging current setting circuit 80..Battery voltage detection circuit 90..Display Circuit 100..Charge voltage control circuit Vc..Charge target voltage value Is..Constant current value Ie..End current value

Claims (17)

A charging device for charging a secondary battery housed in a battery pack,
The battery pack
Corresponding value calculating means for calculating a corresponding value corresponding to the charge capacity of the secondary battery;
Storage means for storing the corresponding value for each charge,
The charging device
Obtaining means for obtaining the corresponding value;
Condition setting means for setting a charging condition based on the corresponding value;
And a charging control unit configured to control charging of the secondary battery using the charging condition. The corresponding value calculation means
Charging current detecting means for detecting a charging current when the secondary battery is charged;
Clock means for measuring the charging time when the secondary battery is charged;
2. The charging device according to claim 1, comprising: a calculation unit that calculates the corresponding value from the charging current detected by the charging current detection unit and the charging time measured by the clock unit. . The charging condition includes a charging target voltage value of the secondary battery,
3. The charging device according to claim 1, wherein the condition setting unit sets the charging target voltage value based on the corresponding value. The charge control means selectively performs constant current charge control for charging the secondary battery with a constant current value and constant voltage charge control for charging the secondary battery with a constant voltage value,
The charging condition includes a constant current value in the constant current charging control,
The charging device according to claim 1 or 2, wherein the condition setting means sets the constant current value based on the corresponding value. The charge control means selectively performs constant current charge control for charging the secondary battery with a constant current value and constant voltage charge control for charging the secondary battery with a constant voltage value, and the constant voltage In the charge control, when the charge current is below the end current value, the charge is terminated,
The charge condition includes the end current value in constant voltage charge control,
The charging device according to claim 1, wherein the condition setting unit sets the end current value based on the corresponding value.   6. The charging device according to claim 1, wherein the condition setting unit sets the charging condition based on an integrated corresponding value that is a value obtained by integrating a plurality of the corresponding values.   The charging apparatus according to claim 1, wherein the condition setting unit sets the charging condition based on a previous correspondence value stored when the battery was last charged. The condition setting means includes:
Setting the charging condition based on an integrated corresponding value which is a value obtained by integrating a plurality of the corresponding values;
If the integration corresponding value is less than a predetermined value, the charging target voltage value is set to the first voltage value,
4. The charging device according to claim 3, wherein when the integration corresponding value is equal to or greater than a predetermined value, the charging target voltage value is set to a second voltage value lower than the first voltage value. . The condition setting means includes:
Set the charging condition based on the previous corresponding value stored at the time of previous charging,
If the previous corresponding value is greater than or equal to a predetermined value, the charging target voltage value is set to the first voltage value,
4. The charging device according to claim 3, wherein, when the previous corresponding value is less than a predetermined value, the charging target voltage value is set to a second voltage value lower than the first voltage value. 5. . The condition setting means includes:
Setting the charging condition based on an integrated corresponding value which is a value obtained by integrating a plurality of the corresponding values;
If the integration corresponding value is less than a predetermined value, the constant current value is set to the first current value,
5. The charging device according to claim 4, wherein when the integrated corresponding value is equal to or greater than a predetermined value, the constant current value is set to a second current value smaller than the first current value. The condition setting means includes:
Set the charging condition based on the previous corresponding value stored at the time of previous charging,
If the previous corresponding value is greater than or equal to a predetermined value, the constant current value is set to the first current value,
5. The charging device according to claim 4, wherein when the previous corresponding value is less than a predetermined value, the constant current value is set to a second current value smaller than the first current value. The condition setting means includes:
Setting the charging condition based on an integrated corresponding value which is a value obtained by integrating a plurality of the corresponding values;
If the integration corresponding value is less than a predetermined value, the end current value is set to a third current value,
6. The charging device according to claim 5, wherein when the integrated corresponding value is equal to or greater than a predetermined value, the end current value is set to a fourth current value that is larger than the third current value. The condition setting means includes:
Set the charging condition based on the previous corresponding value stored at the time of previous charging,
If the previous corresponding value is greater than or equal to a predetermined value, the end current value is set to a third current value,
6. The charging device according to claim 5, wherein when the previous corresponding value is less than a predetermined value, the end current value is set to a fourth current value that is larger than the third current value. A charging device for charging a secondary battery housed in a battery pack,
A charging device that changes a charge control value in accordance with a past charge capacity of the secondary battery.   The charging device according to claim 14, wherein the charging capacity is a charging capacity at the time of previous charging.   The charging device according to claim 14, wherein the charging capacity is an accumulated charging capacity charged in the past.   The charging device according to any one of claims 14 to 16, wherein the charging control value is at least one of a charging voltage value, a charging current value, and a termination current value.

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