JP3511927B2 - Charge / discharge device for power storage means - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging / discharging device for power storage means and a method for manufacturing power storage means using the same.

[0002]

2. Description of the Related Art In lithium-ion secondary batteries and nickel-hydrogen secondary batteries, for the purpose of inspecting secondary batteries after assembly and activating chemical reactions, charging processing of single cells, charging and discharging processing, etc. Is applied. Conventionally, in the charging and discharging of the battery after such assembly, when a defective battery is detected, it is necessary to select the battery individually, so that an independent charging and discharging power source is provided for each battery to charge and discharge the battery. Running. In particular, with lithium-ion secondary batteries, it is necessary to perform not only constant-current charging but also constant-voltage charging at the time of charging. Therefore, an individual charging power supply system that can set the charging current and charging voltage for each battery is used. . On the other hand, when the individual secondary batteries are used as storage batteries for electric vehicles or electric power storage, the assembled batteries are formed by connecting single cells in series, and by applying a voltage to both terminals in the series connected state, the assembled battery is formed. It is charged and discharged to extract power. In addition, when charging or discharging the batteries connected in series, the same charging current flows through each battery, so if there is a variation in the capacity of each battery, the variation in the individual battery voltage will vary. Occur. Especially in the lithium-ion secondary battery,
It is necessary to keep the voltage of each battery below a predetermined value for charging. Therefore, as in the technique described in Japanese Patent Application Laid-Open No. 8-88944, a method of charging / discharging with a battery pack in a multi-series state is known. In order to suppress the variation in each battery connected in series, each battery is provided with an individual power source for correction.

[0003]

However, when each unit cell is charged or discharged by an individual charge / discharge power source, a charge / discharge power source proportional to the number of unit cells simultaneously charged or discharged is required. Become. In particular, in a charging / discharging device for the purpose of activation and inspection of the assembled secondary battery, a series of charging / discharging processes takes several hours or longer. It is necessary to charge and discharge a large number of single cells at the same time by using the charge and discharge power supply of.
For this reason, there is a problem in that a large number of individual charging / discharging power supplies are required, although it is sufficient to charge / discharge each unit cell with a similar current and voltage pattern.

In addition, as in the case of application to an electric vehicle or a storage battery for storing electric power, a battery pack is formed by connecting a plurality of unit cells in series, and in this state, charging or discharging is performed by a power source for collective charging or discharging. In such a method, a circuit for bypassing a defective battery detected during charging / discharging is required for each individual battery. Further, in order to compensate for the voltage variation due to the capacity variation of individual cells and charge or discharge so that the voltage of each cell becomes uniform, an individual charge / discharge power source is required for each cell. Become. In addition, especially in the lithium-ion secondary battery, while accurately measuring each battery voltage,
It is necessary to charge and discharge. In the state where individual cells are connected in series, it is necessary to detect the voltage of each battery by a differential potential, which causes a problem that a circuit for voltage detection becomes complicated.

Further, when a plurality of batteries are connected in parallel to charge and discharge, charging and
Alternatively, the discharge current is not uniform, each battery cannot be fully charged, and an additional circuit for detecting and disconnecting a defective battery is required.

The present invention has been made in consideration of the above problems.

[0007]

A charging / discharging device for power storage means according to the present invention comprises an AC power supply, a transformer having a primary winding to which the AC power supply is connected and a plurality of secondary windings, and an AC power supply for each of them. A plurality of power converters each having a side connected to one of the plurality of secondary windings and each DC side connected to one of the plurality of power storage means.

According to the present invention, the power storage means is connected to each of the plurality of secondary windings of the transformer to which the AC power supply is connected, so that the plurality of power storage means are collectively charged or stored by the AC power supply. It enables a collective discharge from the means to the AC power supply.

The charging / discharging device of the power storage means according to the present invention includes a device having a charging function, a device having a discharging function, and a device having both functions. Further, as the AC power supply, various kinds of devices that output AC power can be applied, but it is preferable to have a power converter unit connected to the primary winding of the transformer. In this case, by controlling the power converter unit so that the current flowing through the primary winding becomes the current command value, it is possible to collectively control the charging or discharging of the plurality of power storage means. Furthermore, examples of the power storage means include a secondary battery , an assembled battery in which a plurality of unit secondary batteries are connected in series , an electric double layer battery , a capacitor, and the like .

In the charging / discharging device for the power storage means according to the present invention as described above, the AC power source is provided with the power converter section, and further the electric motor and the inverter which is supplied with electric power from the electric power converter section and drives the electric motor. By including and, it is possible to construct an electric motor drive system. Further, in the charging / discharging device of the power storage means according to the present invention as described above, a power storage system can be constructed by connecting an AC power supply to the power system.

Next, in the method of manufacturing the power storage means according to the present invention, the first step of assembling the main bodies of the plurality of power storage means and the plurality of powers in the charging / discharging device of the power storage means according to the present invention as described above. The second step of connecting one of the assembled plurality of power storage means to each DC side of the converter, and the charging / discharging device of the power storage means according to the present invention causes the power storage means to be initially connected to the plurality of power storage means. A third step of performing charging, initial discharge, or aging treatment.
According to the present invention, in the manufacturing process of the power storage means, it is possible to collectively perform the initial charge, the initial discharge, or the aging process on the plurality of power storage means by the AC power source. Preferably, the AC power supply has a power converter unit connected to the primary winding of the transformer. In this case, by controlling the power converter unit so that the current flowing through the primary winding becomes the current command value, it is possible to collectively control the initial charging, the initial discharging, or the aging process of the plurality of power storage units. .

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, as a first embodiment of the present invention, a case of collectively charging n (n: 2 or more) secondary batteries will be described with reference to FIG. In FIG. 1, the output of the AC power supply 1 is connected to the primary side of a transformer 2 as a transformer, and the transformer 2 outputs n secondary windings 201, 202 and 203. Here, in the transformer 2, primary windings of a plurality of transformers are connected in series, and the output of the AC power supply 1 is applied to both ends thereof. Further, each secondary side output of the transformer 2 is output to the plurality of unit cells via the AC / DC converting means 3 composed of n individual AC / DC converters. AC power supply 1
The AC voltage of the three-phase commercial power supply 101 is rectified by the rectifier diode converter 102, and the output is smoothed by the smoothing capacitor 103.
The full-bridge converter 104 converts a DC voltage obtained by smoothing the AC voltage into an AC voltage having a desired frequency. Here, the voltage of the commercial three-phase power supply is AC200.
At V, the DC voltage is about 280V. The full-bridge converter is a semiconductor switching element I
It is composed of a GBT (Insulated Gate Bipolar Transistor), and the frequency of the AC output voltage is 20 kHz.

The secondary side circuit of the transformer 2 is a rectifying diode bridge 311, 321, 33 provided for each battery.
1 and reactors 312, 322, 332 connected to the DC output of each diode bridge, converting the AC voltage on the secondary side of the transformer into a DC voltage,
A charging current is supplied to each secondary battery 4, 5, 6. here,
When the turns ratio of the windings individually coupled to the primary side and the secondary side of the transformer is set to 1: a, the currents of the primary side windings connected in series and the respective outputs of the transformer secondary side are The ratio with the current is a: 1. The primary side current and the plurality of secondary side currents flow while maintaining this relationship, regardless of variations in battery voltages, internal resistance, and the like. Therefore, by controlling the full-bridge converter 104 so that the primary side current of the transformer matches the desired command value, it is possible to collectively control the secondary side current of the transformer. In each secondary circuit, switches Y11, Y21, Y31 for short-circuiting the outputs of the rectifying diode bridges 311, 321, 331, and a switch Y1 for disconnecting the connection between the batteries 4, 5, 6 are provided.
2, Y22, Y32 are provided respectively, and individual control signals 313, 323, 3 from the individual control device 304 are provided.
According to 33, each of these switches is on / off controlled.

Next, operation waveforms are shown in FIG. The full bridge converter 104 outputs an alternating voltage that alternates at a high frequency of 20 kHz. As shown in FIG. 2A, by comparing a triangular wave carrier signal having the same frequency as the output frequency of the full-bridge converter 104 with a signal representing the positive voltage command and the negative voltage command, the gate of the IGBT is compared. The drive signals s1, s2, s3, s4 are obtained. Where s
Since 1 and s3 and s2 and s4 are turned on / off in a complementary manner, a non-wrap period of about several μs is provided.
By driving the IGBT of the full bridge converter 104 with this signal, the AC voltage shown in FIG. 2C is obtained. This AC output has a peak value of Vdc and a period of 50μ.
At s, the duty ratio becomes a rectangular wave voltage proportional to the magnitude of the voltage command on the positive side and the negative side. Examples of AC voltage waveforms when the conduction ratio is changed are shown in FIGS. 3 (a) and 3 (b). By applying this AC voltage to the primary side of the transformer 2, a voltage obtained by dividing the primary side voltage by the number n of multiple series is output to each secondary side output. The voltage sharing of the secondary side output is determined depending on each battery voltage and the like. This secondary voltage is rectified by the rectifying diode bridges 311, 321, 331 and converted into a DC voltage, and the reactor 31 is converted by the difference between this voltage and the battery voltage.
A charging current is passed through 2,322,332. When viewed from the full-bridge converter 104, the batteries of the secondary circuit of the transformer 2 are connected in series via AC. Therefore, the current flowing to the primary side and the charging current to the battery connected to each secondary circuit are in the relation of the number of turns, and the charging current of each battery varies in battery voltage and internal resistance. Are equal. Therefore, by controlling the current of the full-bridge converter 104, the charging current to each battery can be controlled. The waveforms of the AC current on the primary side of the transformer and the charging current to each battery at this time are shown in FIGS. 4 (d) and 4 (e). From this, the charging current and the AC current on the transformer primary side are s4 and s1 turned on or s2 and s3 among the gate signals to the full bridge converter 104.
Matches while is on. Therefore, the alternating current is
As shown in (f), it is detected by the current detector 105 (CT in this embodiment) in synchronization with the minimum amplitude time point of the gate signal generating carrier signal (valley of the triangular wave carrier signal), and the detected value is detected. By holding until the next detection time, the charging current to each battery can be detected from the AC current on the primary side of the transformer. By using the current detection value on the transformer primary side, the duty factor of the full-bridge converter is controlled so that the current detection value becomes the charging current command value, thereby charging the secondary battery connected to the transformer secondary side. Even if there is a variation in the voltage or internal resistance of each battery, the current can be controlled to be the same charging current among the batteries. Here, since the secondary sides of the transformers are insulated from each other, each battery can individually ground one side of the terminals to a common potential, and thus the battery voltage can be detected with respect to the common potential.

Next, in this embodiment, since the batteries are charged in a state of being connected in series via a transformer, if a defective battery is detected during charging, the corresponding battery is disconnected from the secondary circuit, and It is necessary to continue charging other batteries. Further, when variations in battery voltage occur during charging, it is necessary to individually bypass the charging current of each battery and adjust the charging current for each battery. The operation waveform at this time is shown in FIG. Now, full bridge converter 104
Output current of Ic, charging current to each battery is I1, I2,
..., In. Here, the switch Y1 on each secondary circuit side
1, Y21, Y31 are off, switches Y12, Y2
When 2 and Y32 are on, each battery is normally charged.
On the other hand, by turning on the switch Y11 of the first secondary circuit, the relevant secondary circuit can be short-circuited, the charging current flows to the switch Y11 side, and the battery 4 can be bypassed. After bypassing the switch Y22,
The battery can be disconnected from the charging circuit. Here, as the switch Y11, a power MOSFET (Metal Oxide Semic
If a semiconductor switching element such as an onductor field effect transistor) is used, the bypass of each battery current can be finely controlled, thereby compensating the current of each secondary circuit. In addition, by individually turning on / off the switches Y11, Y21, and Y31, the full bridge converter 10
Although the load changes when viewed from 4, the output current of the full-bridge converter 104 can be controlled to a desired value by controlling the output current of the full-bridge converter 104.

As described above in detail, according to this embodiment, a plurality of batteries on the secondary side of the transformer can be collectively charged in a series connection by the transformer having the primary side connected in multiple series. There is an advantage that the circuit configuration is simple as compared with the case of individually charging with each power source. Further, since charging is performed in a state where battery voltages are connected in series, there is an advantage that a plurality of batteries can be collectively charged without increasing the current, and efficient batch charging can be performed. Also, since the batteries connected to the secondary side of the transformer are insulated from each other,
The voltage of each battery can be measured against a common potential,
There is also an advantage that it is easy to measure a plurality of battery voltages. In addition, by detecting the current on the transformer primary side in synchronization with the switching operation of the full-bridge converter, and using the result to control the magnitude of the output current of the full-bridge converter to match the desired charging current command value. The advantage is that the charging current can be controlled collectively regardless of the number of secondary side circuits. In addition, since the value at the almost midpoint of the current ripple due to the duty ratio control of the full-bridge converter can be detected as the current detection value, there is an advantage that the current detection can be executed without the influence of the current ripple of the charging current. Further, according to the present embodiment, any battery in which a defect is detected can be disconnected from the charging circuit even during charging, so that the defective battery can be disconnected while continuing to charge the other batteries. Further, there is an advantage that the charging current of each battery can be individually compensated by using the function of bypassing the charging current and the variation of the battery voltage can be corrected.

Next, a second embodiment of the present invention will be described with reference to FIG. Reactors 312, 322, 332 are connected to the outputs of the batteries 4, 5, 6, respectively,
The output is the full bridge converters 315, 325, 3
At 35, it is converted into an AC voltage and each is supplied to a plurality of secondary windings of the transformer. Here, the full-bridge converter is composed of power MOSFETs. Transformer 2
The primary winding is connected in multiple series to the corresponding secondary winding, and the output voltage of the primary winding is converted by the converter 10
7. By operating the booster chopper by the control circuit 108, the electric power charged in each battery is supplied to the smoothing capacitor 10
3. The power is regenerated to the power supply 101 via the regenerative converter 109 and the reactor 110. FIG. 7 shows the gate signals of the full-bridge converters 315, 325, 335 and the gate signal on the converter 107 side for each battery at this time. As shown in FIGS. 7 (c) and 7 (d), the converter 107 sets the I of the negative arm at a predetermined chopper cycle.
The gate signals s3 and s4 of the GBT element are turned on / off.
Here, during the on period of s3 and s4, the battery on the secondary side of the transformer is short-circuited via the reactors 312, 322, 332. On the other hand, during the off period of s3 and s4, the power stored in the reactor of each battery is the smoothing capacitor 103.
Emitted to the side. Here, the full-bridge converters 315, 325, and 335 for each battery are configured such that the DC voltage of each battery is an AC voltage whose frequency and magnitude are fixed (here, the magnitude of the AC voltage is proportional to the battery voltage). Convert to.
Therefore, the same gate signal is applied to the full-bridge converters of all the batteries in synchronization with the carrier signal for generating the gate signal of the converter 107, as shown in FIGS. In addition, the full bridge converter 315,
When the power MOSFETs 325 and 335 are switched on / off, a short-circuit period signal that short-circuits the upper and lower arms is given. As a result, the reactor current for each battery can be continuously controlled even when the polarity of the alternating current is switched. Further, by setting this short circuit signal so as to be synchronized with the on period of the chopper control signal of the converter 107, it is possible to provide the short period during the polarity switching of the full bridge converter in the on period of the boost chopper. This allows
The battery voltage can be converted into an alternating current for each battery without affecting the step-up chopper operation, and the discharge can be collectively performed in a state in which the batteries are connected in multiple series by the transformer 2. In addition, even during discharge, in synchronization with the ON period of the boost chopper,
By detecting the alternating current on the primary side of the transformer, the current value corresponding to the discharge current of each battery can be detected by detecting the current on the primary side of the transformer. These operations have the same relationship as the detection of the charging current from the primary side of the transformer during collective charging.

As described above in detail, according to the second embodiment, the battery voltage is converted into an alternating current, and the step-up chopper control can be executed in the state where the voltage is connected in series by the transformer. The collective discharge can be executed without providing a discharging power source for the battery, and the collective discharge can be executed with simple control. Also, by synchronizing the gate signal for boost chopper control and the gate signal for the full-bridge converter for converting each battery into an AC voltage, it is possible to be affected by the short-circuit period associated with the AC conversion of each battery voltage. There is an advantage that a batch discharge can be performed without using.

A third embodiment of the present invention will be described with reference to FIG. Full-bridge converter 104 for collective charge / discharge, full-bridge converters 315, 325, 335 for each battery
However, it differs from the first and second embodiments. In this way, by making both converters full bridge converters, by controlling the gate signals to them, collective charging, collective charging, and disconnection of defective batteries, collective charging, individual charging control, collective discharging, collective charging Discharge and individual discharge control can be executed respectively.

As described above, according to the third embodiment, there is an advantage that charge / discharge control in each operation mode can be switched and executed by controlling each gate signal with the same circuit configuration. .

A fourth embodiment of the present invention will be described with reference to FIG. In this embodiment, an individual discharge power source 7 for each battery is added to the first embodiment shown in FIG.
The individual discharge power source is connected between each output of the individual DC / AC converter 3 (that is, between the terminals of each battery) and the smoothing capacitor 103. In addition, each individual discharge power source,
It is composed of a current-controlled isolated switching power supply. In this configuration, at the time of charging, the full-bridge converter 104 causes the collective charging current Ic2 for each battery.
Is supplied. On the other hand, an individual current command value is given to the individual discharge power source, and accordingly, Id1, Id2, Id3
Is regenerated from each battery to the smoothing capacitor side. Therefore, the charging current to each battery is a current obtained by subtracting the currents Id1, Id2 and Id3 to the individual discharging power source from the batch charging current value Ic2. As a result, the charge current of each battery can be corrected according to variations in battery capacity by operating the individual discharge power supply during collective charging. On the other hand, at the time of discharging each battery, the discharge currents Id1, Id2, Id3 can be regenerated from each battery to the power supply 101 side by the individual discharging power supply 7. As a result, collective charging, individual charging control, and individual discharging can be executed. The operation waveform at this time is shown in FIG.

As described above in detail, according to the fourth embodiment, since the compensation including the individual charging control at the time of collective charging can be executed by the individual discharging power source for discharging, it is possible to charge with a simple circuit configuration. Discharge control can be achieved. In addition, since an individual power supply with a large boosting ratio is used for discharging, there is also an advantage that discharge control of each battery can be executed in a wide battery voltage range including a state where the battery voltage is low.

Next, a fifth embodiment according to the present invention will be described with reference to FIG.
Shown in. The difference from the fourth embodiment of FIG. 9 is that a power supply for individual discharge capable of discharging each battery is added to a charging / discharging device capable of performing collective charging / discharging. According to the present embodiment, the power supply for individual discharge is added to the full-bridge converter capable of collective charge and collective discharge, so that the power supply capacity for individual discharge is suppressed to a small capacity that can correct the variation in battery capacity. There is an advantage that you can.

As described above, according to the fifth embodiment, there is an advantage that the power supply for individual discharge can be limited to a small capacity for correcting the capacity variation.

FIG. 12 shows the configuration of the sixth embodiment according to the present invention.
Shown in. The transformer 8 is different from the third embodiment shown in FIG.
And the individual AC / DC converting means 3 to each converter 31
.. and bidirectional chopper circuits 318, 328, 338 connected between the batteries 4 ... Here, the transformer 8 has a configuration in which a plurality of secondary windings are connected in parallel to the primary winding, and the transformer 2 is connected in multiple series, whereas in the present embodiment, it is connected in multiple parallel. ing. In this embodiment, the AC output voltage of the full bridge converter 104 is output in parallel to the plurality of secondary windings during charging. Full bridge converter 1
An output voltage setting value is commanded to 04, and an AC output voltage is output according to this setting value. Individual AC / DC converter 3
Controls the charging / discharging of each battery by individually controlling the charging / discharging of each battery using each output voltage of the transformer 8 as an input. On the other hand, during discharge, the full bridge converter 104
The gate signal for each IGBT is turned off, and operates as a rectifying diode bridge. The discharge current of each battery is converted into AC by the individual AC / DC converter 3, and the transformer 8
Are connected in parallel by. Full bridge converter 10
By the rectifying diode operation of No. 4, the discharge current of each battery is collectively regenerated to the smoothing capacitor 103 side, and the power regeneration converter 109 regenerates the commercial power source 101.

FIG. 13 shows operation waveforms during charging in this embodiment. The operation of FIGS. 13A to 13C is similar to that of the multi-series connection method in the first to fifth embodiments, but the output voltage command value for the full bridge converter 104 is directly given as the output voltage set value. To be Here, the output voltage setting value is set according to the magnitude of each battery voltage. That is,
Since the battery voltage is small at the initial stage of charging, the output voltage set value for the full-bridge converter 104 is small, and the output voltage set value is large near full charge. On the other hand, in the individual charge / discharge control 307, the current detecting means 319, 32 of each battery
9, 339 detects the charging / discharging current of each battery, and controls the gate signals m11, m21, ..., Mn1 of the power MOSFETs of the positive arm of the bidirectional chopper circuits 318, 328, 339. This operation waveform is shown in FIG. That is, the individual control amount is calculated as a result of the individual charge / discharge control 307 for each battery, and the m11, m21, ..., Mn1 signals are obtained by comparing the levels with the toothed waves. Thus, the AC voltage generated by the full-bridge converter 104 is turned off while m11, m21, ..., Mn1 are off, so that the charging voltage can be corrected for each battery. The AC output waveform at that time is shown in FIG.
Shown in. With respect to the output voltage of the full-bridge converter shown in FIG. 13C, the conduction ratio of the AC voltage is corrected by the individual correction amount shown in FIG. 13D . By performing this correction for each battery, it is possible to correct variations in the battery voltage, variations in the voltage sharing of the transformer, and the like to compensate so that the charging current to each battery is maintained at a desired value. The waveform of the individual charging current at this time is shown in FIG. As a result, as in this embodiment, it is possible to control the current flowing through the plurality of secondary side circuits connected in multiple parallel via the transformer to be constant. Even when the charging current for each battery is corrected, the charging current to each battery can be controlled by using the voltage adjusting function of the bidirectional chopper circuits 318, 328, 338.

On the other hand, FIG. 14 shows operation waveforms during discharge.
Unlike the case of the third embodiment shown in FIG. 8, each full-bridge converter 104 operates as a rectifying diode bridge, and the individual AC / DC converter 3 controls the discharge current of each battery individually. To control. At the time of discharging, the battery voltage is changed by turning on / off the gate signals m12, m22, ... To lower the voltage. Thereby, the discharge current can be controlled individually for each battery. The operation waveform at this time is shown in FIG. here,
The individual control amount that gives the flow rate of the gate signals m12, m22, ..., Mn2 is calculated as a result of the discharge current control in the individual charge / discharge control 307. As a result, the full-bridge converter 104 can be collectively discharged by the rectifying diode operation, and by the gate signals m12, m22, mn2 of the lower arms of the bidirectional chopper circuits 318, 328, 338,
Even when the battery voltage varies, the discharge current can be controlled to a desired constant value.

As described above in detail, according to the fifth embodiment, a plurality of batteries connected in parallel via the transformer 8 can be collectively charged and discharged, so that the charge and discharge circuit structure can be simplified. There is an advantage. In addition, since a transformer in which a plurality of secondary windings are coupled in parallel with the primary winding can be integrally configured with a magnetic core, it is not necessary to provide the transformer in proportion to the number of secondary windings. There is also. Further, by providing the bidirectional chopper circuit in each secondary side circuit, there is an advantage that the charging current and the discharging current of each battery can be controlled according to a desired command value or can be individually compensated.

Next, a method of manufacturing a secondary battery will be described as an example of the present invention. In the secondary battery manufacturing process, initial charging, discharging, and aging are performed on the assembled battery.

The outline of the manufacturing process of the non-aqueous electrolyte secondary battery will be described below. In such a secondary battery, a positive electrode active material and a negative electrode active material are applied to predetermined foils, respectively, a separator is put between them, and they are wound up, inserted into a predetermined can, filled with an electrolytic solution, and sealed. Assembly is complete. Here, in the positive electrode, first, cobalt lithium oxide, a carbon material-based conductive agent, and the like are dissolved in an organic solvent to form a paste, and this mixture is applied to both sides of the aluminum foil. After this is dried, it is compressed by a roll press.

On the other hand, carbon or graphite is used as the negative electrode agent, and a mixture with a binder is kneaded into a paste, bound to a copper foil, and similarly wound. Next, in a winding step, both electrodes are wound via a separator and cut. The wound electrode is housed in a battery can, welded to a sealing cap, injected with an electrolytic solution, and then sealed to complete the assembly process of the battery body.

In addition, the assembled battery has an initial charge / discharge,
Also, an aging process of leaving the battery in a charged state is performed. That is, the assembled battery is charged and discharged. After being initially charged to a predetermined voltage, it is discharged to a predetermined voltage and then left to stand. This provides a method for manufacturing a non-aqueous electrolyte secondary battery capable of confirming the capacity and suppressing deterioration of the charge / discharge cycle of the battery after aging.

The initial charging / discharging device according to the present invention has an advantage that such charging / discharging control can be collectively controlled. Here, the charging / discharging characteristics of a large number of batteries are executed as follows. During initial charging, a plurality of test batteries are installed in the charging / discharging device. The charging / discharging device supplies a charging current to a plurality of batteries according to a predetermined charging current command value. During charging, each battery voltage is measured by the voltage detection means of the charging / discharging device, and each battery voltage sequentially forms a charging current bypass circuit from the battery that has reached a predetermined set voltage, and The battery voltage makes it possible to change the current command value for each battery with respect to the charging current. Here, the charging current is set to a constant value on the batch converter side, and the charging is completed up to a predetermined value from the charged battery to the battery that is sequentially disconnected from the charging circuit and the last one battery is completed. . As a result, it becomes possible to collectively control the discharge while maintaining the voltage of each battery constant both during charging and during discharging.

Next, after charging a plurality of battery voltages to a predetermined voltage value, initial charging is completed, and then initial discharging is performed.
Discharge is continued until each battery voltage decreases to a predetermined voltage. At this time, the discharge current command value continues discharging so that the discharge current is common to all the batteries. Here, even if discharged with the same discharge current due to variations in battery capacity,
A difference occurs in the time required to reach the discharge completion voltage.
In this case as well, similar to the individual disconnection at the time of charging, the battery completely discharged up to a predetermined discharge end voltage by the discharge is disconnected from the batch discharge state. This is because by turning on the bypass circuit on the side of the individual converter, the discharge current can be bypassed to the corresponding battery, whereby the discharge of each battery can be completed up to the discharge end voltage. After the charging, discharging and processing are completed in a batch, the charging / discharging circuit is disconnected and the aging processing is started. Next, the voltage lowered during the aging period is charged again to complete the charging / discharging process.

As described in detail above, according to the charging / discharging device or method of the present invention, in the battery manufacturing process,
It is possible to perform initial charge / discharge processing and aging processing collectively.

Next, as an embodiment of the present invention, a charging / discharging device for assembled batteries connected in multiple series is shown in FIGS. 15, 16 and 17. The structure of the charging / discharging device is the same as that of any one of the embodiments described so far, except that the assembled battery is charged / discharged with respect to the single battery. In the embodiment shown in FIG. 15, the battery packs are connected in multiple series via the transformer 2, and the full bridge converter 1 is connected.
The battery is collectively charged and discharged by 04. Further, in the embodiment of FIG. 16, the assembled batteries are connected in multiple parallel via the transformer 8, and the full bridge converter 104 collectively charges and discharges. Also, FIG.
In the seventh embodiment, a plurality of battery packs connected in series via a transformer 13 are connected in multiple parallel, and the full bridge converter 104 collectively charges and discharges them. As described above, even in a battery pack in which the unit cells are connected in multiple series, there is an advantage that a plurality of battery packs can be charged / discharged with a simple structure by collectively charging / discharging via the transformer.

Next, as another embodiment of the present invention, an application example to an electric vehicle is shown in FIGS. In FIG. 18, a plurality of assembled batteries 9, 10, 11 are connected in multiple series via a transformer 2. By discharging the energy of the assembled battery by the batch converter 12, the electric power of the battery is supplied to the induction motor through the inverter 12 connected to the DC side of the converter 12 through the converter 12 and the inverter 13 to drive the electric vehicle. To drive. On the other hand, by supplying a DC voltage to the batch converter 12 by the charger 15, the batch converter 12 charges each battery with a charging current via the transformer 2. 19 shows the transformer 8
Shows the case of multiple parallel connection. According to this embodiment,
Since a plurality of assembled batteries can be combined in an insulated state and charged and discharged, there is an advantage that the assembled batteries can be divided and managed and individually replaced. Furthermore, by dividing the assembled battery, there is an advantage that the voltage and the total capacity of the assembled battery can be limited.

The embodiments of FIGS. 18 and 19 can be applied not only to electric vehicles but also to various induction motor drive systems. In addition to the induction motor, the system of this embodiment can be applied to any motor driven by an inverter such as a brushless motor.

Next, as another embodiment of the present invention, an application example to a power storage system is shown in FIGS. Figure 20
In the above, the assembled batteries 9, 10, 11 which are electric power storage means are connected in multiple series by the transformer 2, and are linked to the electric power system 16 via the collective converter 1. Further, FIG. 21 shows a case where the transformers 8 are connected in multiple parallel. According to this embodiment, there is an advantage that each battery pack is divided and arranged, and that each battery pack can be easily replaced.

[0040]

According to the present invention, it is possible to charge and discharge a plurality of secondary batteries of two or more and the assembled battery thereof at a time. Therefore, each individual battery or the assembled battery can be charged and discharged by an individual charge / discharge power source. The charging / discharging device can be configured with a simpler structure than the case of individually charging and discharging. Further, in batch charging, since the batteries can be charged or discharged in a state of being connected in multiple series or in multiple parallel, charging or discharging can be performed in a state where the output voltage of the converter for charging / discharging is high. Therefore, there is an effect that the current capacity of the power element forming the converter and the copper loss due to the current flowing through the converter can be reduced, and an efficient charging / discharging power supply can be formed.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a charging power source according to a first embodiment.

FIG. 2 is an operation waveform of the charging power source according to the first embodiment.

FIG. 3 is an operation waveform of the charging power source according to the first embodiment.

FIG. 4 is an operation waveform of the charging power source according to the first embodiment.

FIG. 5 is an operation waveform of the charging power source according to the first embodiment.

FIG. 6 is a configuration diagram of a discharge power supply according to a second embodiment.

FIG. 7 is an operation waveform of the discharge power supply according to the second embodiment.

FIG. 8 is a configuration diagram of a charging / discharging power source according to a third embodiment.

FIG. 9 is a configuration diagram of a charging / discharging power source according to a fourth embodiment.

FIG. 10 shows operation waveforms of the charge / discharge power supply according to the fourth embodiment.

FIG. 11 is a configuration diagram of a charge / discharge power supply according to a fifth embodiment.

FIG. 12 is a configuration diagram of a charging / discharging power source according to a sixth embodiment.

FIG. 13 is an operation waveform of the charging / discharging power source according to the sixth embodiment.

FIG. 14 is an operation waveform of the charging / discharging power source according to the sixth embodiment.

FIG. 15 is a battery pack charge / discharge device according to an embodiment of the present invention.

FIG. 16 is a battery pack charge / discharge device according to an embodiment of the present invention.

FIG. 17 is a battery pack charging / discharging device that is an embodiment of the present invention.

FIG. 18 is an example of application to an electric vehicle that is an embodiment of the present invention.

FIG. 19 is an application example of the present invention to an electric vehicle.

FIG. 20 is an application example of the power storage system according to the embodiment of the present invention.

FIG. 21 is an application example of the power storage system according to the embodiment of the present invention.

[Explanation of symbols]

1 ... AC power supply, 2 ... Multiple series connection transformer, 3 ... AC / DC converter.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hideki Miyazaki, Inventor Hideki Miyazaki 7-1, 1-1, Omika-cho, Hitachi-shi, Ibaraki Hitachi Ltd. (72) Inventor Akihiko Emori 7-chome, Omika-cho, Hitachi-shi, Ibaraki No. 1 in Hitachi Research Laboratory, Hitachi, Ltd. (56) Reference JP-A-9-46913 (JP, A) JP-A-9-117067 (JP, A) JP-A-56-88630 (JP, A) JP-A-SHO 48-43138 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H02J ⁷ /00-7/12 H02J 7/34-7/36 H01M 10/44

Claims (6)

(57) [Claims] 1. An AC power supply, first AC / DC power conversion means connected to the AC power supply, and second DC / AC power conversion means connected to the DC output of the first AC / DC power conversion means. A plurality of transformer primary windings are connected in series to the AC output terminal of the second DC / AC power converting means, and rectifiers are connected to the secondary windings of the plurality of transformers, respectively.
A power storage means is connected to the output of each of the rectifiers via a first switch means, and a second switch means for short-circuiting the output of the rectifier is provided, and the first AC / DC power conversion means is provided. The second DC / AC converting means is a bidirectional power converting means for converting alternating current into direct current or converting direct current into alternating current. 2. The charging / discharging device of the power storage means according to claim 1, wherein the second DC / AC power conversion means controls the current flowing through the primary winding of the transformer to be a current command value. A charging / discharging device for power storage means, comprising: 3. The charging / discharging device for power storage means according to claim 2, wherein the first switch means provided on the secondary winding side of the plurality of transformers are individually opened to store the plurality of power storages. A charging / discharging device for power storage means, wherein the means can be individually separated from the rectifying unit. 4. An AC power supply, a first AC / DC power conversion means connected to the AC power supply, and a second DC / AC power conversion means connected to a DC output of the first AC / DC power conversion means. A plurality of transformer primary windings are connected in series to the AC output terminal of the second DC / AC power converting means, and rectifiers are connected to the secondary windings of the plurality of transformers, respectively.
The power storage means is connected to the output of each of the rectifiers via the first switch means, and the second switch means for short-circuiting the output of the rectifier is provided, and the power storage means and the first switch are provided. A charging / discharging device for the power storage means, characterized in that the discharge means of the power storage means is disposed between the AC side and the DC side of the power conversion means. 5. The charging / discharging device for the power storage means according to claim 1, wherein the discharging means of the power storage means is provided between each of the power storage means and the DC side of the first AC / DC power conversion means. A charging / discharging device for power storage means, which is characterized by being arranged. 6. The charging / discharging device for the power storage means according to claim 4 or 5, wherein the discharge is arranged between the power storage means and the DC side of the first AC / DC power conversion means. A charging / discharging device for power storage means, wherein the means is an insulating switching power supply.