JP2010182579A - Electric power source device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric power source device for a vehicle capable of discharging inexpensively energy of a battery when disposed. <P>SOLUTION: This electric power source device for the vehicle includes a battery pack 40 including a plurality of secondary batteries, an equalizing circuit 50 for short-circuiting between electrodes of the plurality of secondary batteries respectively, in order to equalize voltages of the plurality of secondary batteries, and a discharge switch SW for progressing the discharge of each of the plurality of secondary batteries, using the equalizing circuit 50, until the plurality of secondary batteries is completely discharged, for disposing the battery pack. The electrodes of the plurality of secondary batteries are connected through resistances respectively, when the discharge switch SW is brought into an ON state, to discharge the respective secondary batteries. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle power supply device, and more particularly to a vehicle power supply device including an assembled battery including a plurality of secondary batteries.

  2. Description of the Related Art In recent years, the development of vehicles equipped with a battery for driving a motor such as an electric vehicle or a hybrid vehicle as a drive source as an environment-friendly vehicle has become active.

  When these vehicles are scrapped vehicles or when batteries are replaced, it is desirable to dispose of the batteries after discharging them so that the terminal voltage of the old batteries is ideally 0 volts.

  Incidentally, Japanese Patent Application Laid-Open No. 2007-214072 (Patent Document 1) discloses a cell voltage measuring device for a fuel cell stack. This measuring apparatus is provided with a resistance provided for each cell of the fuel cell, and it is disclosed that the fuel cell is discharged using this resistance.

JP 2007-214072 A JP 2008-176967 A

  In general, an electric vehicle or a hybrid vehicle that does not include a fuel cell does not include a cell voltage measuring device for a fuel cell stack as disclosed in Japanese Patent Application Laid-Open No. 2007-214072.

  For example, in order to ensure safety after use, it may be possible to attach a discharge resistor and a discharge switch to the assembled battery. However, adding a discharge resistor dedicated to disposal processing increases costs. Further, if one discharge resistor is attached to the entire assembled battery, when there is a variation in the charge amount of each cell, each cell is not discharged safely and electrical energy remains. Moreover, it is not possible to confirm from the outside whether or not electric energy remains with only the discharge resistor.

  An object of the present invention is to provide a vehicle power supply device capable of discharging battery energy at the time of disposal at low cost.

  In summary, the present invention is a power supply device for a vehicle, and includes an assembled battery including a plurality of secondary batteries, and electrodes for each of the plurality of secondary batteries in order to equalize the voltages of the plurality of secondary batteries. An equalization circuit for short-circuiting between them, and a discharge switch for advancing the discharge of each of the plurality of secondary batteries using the equalization circuit until the plurality of secondary batteries are completely discharged to discard the assembled battery Is provided.

  Preferably, the equalization circuit simultaneously connects the plurality of resistors respectively corresponding to the plurality of secondary batteries and the positive and negative electrodes of the corresponding secondary battery according to the operation of the discharge switch. It includes an individual switch and a voltage sensor that detects the voltage of the assembled battery when a plurality of resistors are connected by the individual switch and visually recognizes the remaining energy state of the assembled battery.

  According to the present invention, it is possible to reliably discharge the electric energy of all the cells of the battery at a low cost.

It is the figure which showed the structure of the vehicle 100 carrying a vehicle power supply device. It is the flowchart which showed the process of the battery disposal process.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

FIG. 1 is a diagram showing a configuration of a vehicle 100 equipped with a vehicle power supply device.
Referring to FIG. 1, vehicle 100 includes a motor 10 for driving wheels, an inverter 20 that supplies a driving current to a stator coil of motor 10, and a battery pack 40 that supplies a power supply voltage to inverter 20. Including. System main relays SMRB and SMRG are provided between the inverter 20 and the assembled battery 40.

The assembled battery 40 includes battery cells C1 to Cn connected in series.
Vehicle 100 further includes an equalization circuit 50 having a discharge circuit for equalizing the voltages of battery cells C1 to Cn included in battery pack 40, voltage meter 60, discharge switch SW, and control device 30. .

  The assembled battery 40, the equalization circuit 50, the discharge switch SW, and the voltage meter 60 are accommodated in the battery pack 200.

  The equalizing circuit 50 includes discharge resistors R1 to Rn connected in series, a switch SR1 connecting one end of the resistor R1 and the positive electrode of the battery cell C1, the other end of the resistor R1, and one end of the resistor R2. The switch SR2 that connects the intermediate tap connected together to the negative electrode of the battery cell C1 and the intermediate tap connected together to the positive electrode of the battery cell C2, and the other end of the resistor R2 and one end of the resistor R3 are connected together. A switch SR3 for connecting the intermediate tap connected to the negative tap of the battery cell C2 and an intermediate tap connected to the positive electrode of the battery cell C3, and an intermediate connected together to the other end of the resistor R3 and one end of the resistor R4 A switch SR4 that connects the tap, the negative electrode of the battery cell C3, and the intermediate tap connected to the positive electrode of the battery cell C4 is included.

  The equalization circuit 50 further includes an intermediate tap connected to the other end of the resistor Rn-3 and one end of the resistor Rn-2, a negative electrode of the battery cell Cn-3, and a positive electrode of the battery cell Cn-2. The switch SRn-2 that connects the connected intermediate taps, the intermediate tap that is connected to the other end of the resistor Rn-2, and one end of the resistor Rn-1, the negative electrode of the battery cell Cn-2, and the battery cell Cn. -1 of the battery cell Cn-1, the switch SRn-1 connecting the intermediate tap connected together with the positive electrode of -1, the intermediate tap connected together with the other end of the resistor Rn-1 and one end of the resistor Rn. A switch SRn connecting the negative electrode and the intermediate tap connected to the positive electrode of the battery cell Cn, and a switch SRn + 1 connecting the other end of the resistor Rn and the negative electrode of the battery cell Cn are included.

  The voltage across the resistors R1 to Rn connected in series is detected by the voltage meter 60. The voltage meter 60 may be a voltage sensor that can be seen from the outside of the battery pack 200 to see whether or not energy remains in the assembled battery, and may or may not include a pointer or the like.

  The discharge switch SW is a switch for forcibly operating the equalization circuit 50. When the discharge switch SW is changed from the off state to the on state, the switches SR1 to SRn + 1 are turned on all at once. When discharge switch SW is in the off state, control device 30 can individually control on / off of switches SR1 to SRn + 1 by control signals SON1 to SONn + 1 corresponding to switches SR1 to SRn + 1, respectively.

  When the vehicle travels, control device 30 controls system main relays SMRB and SMRG to be in a conductive state, and issues a command to inverter 20 to generate a rotating magnetic field in the stator coil of motor 10.

  Further, when the voltage variation occurs in the battery cells C1 to Cn in the assembled battery 40, the control device 30 conducts necessary switches using the control signals SON1 to SONn + 1, and the voltage becomes higher than the other battery cells. The discharged battery cell is discharged. A cell voltage equalization process is executed by this discharge. This voltage variation of the battery cells occurs because each battery cell has a different self-discharge rate. A battery cell having a large self-discharge has a lower cell voltage than other battery cells.

FIG. 2 is a flowchart showing a battery disposal process.
Referring to FIGS. 1 and 2, when the process is first started, the worker fixes discharge switch SW in the on state in step S1. Then, the equalization circuit 50 operates in step S2, and discharge of the battery cells C1 to Cn is started.

  In step S3, the operator checks whether or not the voltage value indicated by the voltage meter 60 has dropped to near zero. If the value indicated by the voltage meter is not close to 0, the ON state of the discharge switch in step S1 and the discharge of each battery cell in step S2 are continued.

  If the value indicated by the voltage meter 60 has dropped to near 0 in step S3, the process proceeds from step S3 to S4. Whether or not the value indicated by the voltage meter 60 has decreased to near zero is determined by whether or not the value indicated by the voltage meter 60 is lower than a predetermined threshold value (reference value) near zero. In step S4, the discharge switch SW is set to an off state. Note that the operation in step S4 may not be performed.

  Subsequently, the assembled battery 40 is removed from the vehicle 100 in step S5. Note that not only the assembled battery 40 but also the battery pack 200 may be removed from the vehicle. Then, the assembled battery 40 discharged in step S6 is discarded. Thus, the process proceeds to step S7, and the battery disposal process ends.

  In the flowchart shown in FIG. 2, the assembled battery is discharged in the state where it is mounted on the vehicle. However, after removing the battery pack 200 from the vehicle, the discharge switch SW is turned on, and the voltage meter 60 becomes close to zero. After confirming this, the assembled battery 40 may be discarded.

  As described above, in the present embodiment, discharge at the time of disposal is executed using the equalization circuit 50 including the discharge circuit. For this purpose, a discharge switch SW for forcibly operating the equalizing discharge circuit of all cells is provided. And the voltage meter 60 is further provided so that the discharge state of the assembled battery 40 can be confirmed.

  Thereby, since the existing cell voltage equalization circuit is used as the discharge circuit, it is not necessary to newly add a discharge circuit, and the battery at the time of disposal can be discharged at low cost.

  In addition, for example, if the cell voltage varies only by connecting both ends of the battery cells connected in series with a resistor, some cells may not be completely discharged. In the present embodiment, since each cell has a discharge circuit, each cell can be completely discharged even when the charge amount of each cell varies.

  Further, by providing the voltage meter 60, the discharge state can be confirmed, and the operator can easily determine whether or not it can be discarded.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  10 motor, 20 inverter, 30 control device, 40 assembled battery, 50 equalization circuit, 60 voltage meter, 100 vehicle, 200 battery pack, C1-Cn battery cell, R1-Rn resistance, SMRB, SMRG system main relay, SR1- SRn switch, SW discharge switch.

Claims (2)

An assembled battery including a plurality of secondary batteries;
An equalization circuit for short-circuiting electrodes with respect to each of the plurality of secondary batteries to equalize the voltages of the plurality of secondary batteries;
A vehicle equipped with a discharge switch for advancing discharge of each of the plurality of secondary batteries using the equalization circuit until the plurality of secondary batteries are completely discharged in order to discard the assembled battery; Power supply. The equalization circuit includes a plurality of resistors respectively corresponding to the plurality of secondary batteries,
In response to the operation of the discharge switch, an individual switch that connects each of the plurality of resistors together between the positive and negative electrodes of the corresponding secondary battery,
2. The vehicle according to claim 1, further comprising: a voltage sensor that detects a voltage of the assembled battery when the plurality of resistors are connected by the individual switch and visually recognizes an energy remaining state of the assembled battery. Power supply.

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