JPH08149700A - Charger - Google Patents

Abstract

PURPOSE: To obtain a charger for charging a battery set, being used as a power supply in the constitution of series-parallel connection, in a short time through a simple circuit. CONSTITUTION: In charging mode, a control section 4 turns switches 10, 11 OFF and turns a switch 12 ON so that secondary batteries (battery set) 1 comprises a series constitution of 10 cells, i.e., a series-series connection, and a charging current flows through a passage of a power supply 2, a diode 14, a switch 15, a cell 101, a switch 12, a cell 102 and the GND when a switch 15 is turned ON.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION When an assembled battery is constructed by using several secondary batteries, the secondary batteries may be connected in parallel for the purpose of obtaining more current. The term "parallel connection" as used herein means that, for example, when a battery pack is configured with 10 secondary batteries, two groups of secondary battery groups, each of which has five batteries connected in series, are connected in parallel, that is, series-parallel connection. Pointing (also referred to as 5 in 2 para). In the following, the description will be given taking the battery pack of 5 parallels and 2 parallels as an example.

As a method of charging a secondary battery, a method called 1C charging is widely used. This is a method for charging a battery with a constant current by using the nominal capacity of the secondary battery as a charging current. For example,
If the nominal capacity of the secondary battery is 500 mA / h, 500 m
Charging is performed with the constant current of A. In the case of the above-mentioned battery pack of 5 parallels and 2 paras, 1C charging means charging with a constant current of 1.0A (500mA × 2).

However, in this 1C charging method, the currents (hereinafter referred to as “branch currents”) flowing through the two systems connected in series of five do not always become equal. Due to the variation of the single cells in the assembled battery, for example, the branch current is 6: 4, that is, 60.
It may be 0 mA and 400 mA. As a result, the five batteries on one side are charged with a current of 1 C or more, which causes heat generation of the batteries and deteriorates the batteries.

In order to avoid such an adverse effect, the following method has been conventionally used. That is, the charging current is reduced. For example, by reducing the charging current to 800 mA, each current value becomes 480 mA and 320 mA even if the branch current becomes 6: 4, and charging of a single cell is 1 C.
Will never cross. In extreme cases, the charging current is 50
It is set to 0 mA, that is, 0.5 C is charged from the whole assembled battery, and the charging of a single cell does not exceed 1 C in any situation.

The charging current is measured. That is, a branch current detection unit is provided to measure the branch current during charging. When the branch current exceeds a predetermined value (1C), charging is stopped or switched to trickle charging. This method is usually used in combination with. Also, trickle charging is about 0.1 C (in this case, 1 A × 0.1 = 100 mA).
Degree) charge.

[0006]

However, conventionally, as described above, the method of reducing the charging current, stopping the charging, or switching to the trickle charging is adopted, so that the charging time is the normal 1C charging. It will be longer than In addition, an unnecessary circuit such as a branch current detection unit is required when parallel connection is not performed.

The present invention has been made under such a background, and an object thereof is to charge an assembled battery used as a power source in a series-parallel connected configuration in a short time and with a simple configuration. It is to provide a charging device to obtain.

[0008]

In order to achieve the above object, a charging device according to claim 1 is a series-type battery in which a plurality of battery groups each including a plurality of series-connected secondary batteries are connected in parallel.
A charging device for charging an assembled battery used as a power source in a parallel connection state, wherein a power supply unit for supplying a charging current to the assembled battery, a series-parallel connection configuration in which a plurality of battery groups are connected in parallel, A switching unit that switches the configuration of the assembled battery between a series-series connection configuration in which a plurality of battery groups are connected in series, and the charging unit that supplies a charging current to the assembled battery to perform charging. And a control means for controlling the switching operation of the switching means so that the battery has a series-series connection configuration.

In order to achieve the above object, in the charging device according to claim 2, the control means according to claim 1 supplies the charging current from the power source to the battery pack to charge the battery pack. The above configuration is a series-series connection configuration, and when it is used as a power source, the switching operation of the switching means is controlled so that the configuration of the assembled battery is a serial-parallel connection configuration.

In order to achieve the above object, in a charging device according to a third aspect of the present invention, the control means according to the first aspect of the invention configures the assembled battery while avoiding a short circuit between the positive terminal and the negative terminal of the battery group. The switching operation of the switching means is controlled so as to form a series-series connection configuration.

In order to achieve the above object, in a charging device according to a fourth aspect, the control means according to the second aspect configures the assembled battery while avoiding a short circuit between the positive terminal and the negative terminal of the battery group. The switching operation of the switching means is controlled so as to have a series-series connection configuration or a series-parallel connection configuration.

[0012]

According to the present invention, the control means of the battery charger according to claim 1, when the charging current is supplied from the power source section to the assembled battery for charging, the assembled battery has a series-series connection configuration. By controlling the switching operation of the switching means, the series-
(EN) An assembled battery used as a power source in a structure connected in parallel can be charged in a short time with a simple structure.

When the charging means supplies a charging current to the battery pack to charge the battery pack, the control means sets the battery pack to a series-series connection structure and uses it as a power supply. When used, by controlling the switching operation of the switching means so as to make the configuration of the assembled battery into a series-parallel connection configuration, the assembled battery used as a power source in the configuration connected in series-parallel in a short time, And to be able to charge with a simple configuration.

According to a third aspect of the present invention, the control means of the charging means includes the switching means of the switching means so as to make the assembled battery into a series-series connection structure while avoiding a short circuit between the positive terminal and the negative terminal of the battery group. By controlling the switching operation, it is possible to charge the assembled battery used as a power source in a series-parallel connected configuration in a short time and with a simple configuration, and to prevent damage to the assembled battery for safety. Allow charging.

According to a fourth aspect of the present invention, the control means of the battery charger is configured so that the assembled battery is configured in a series-series connection configuration or a series-parallel connection configuration while avoiding a short circuit between the positive terminal and the negative terminal of the battery group. By controlling the switching operation of the switching means, it is possible to charge the assembled battery used as a power source in a configuration connected in series-parallel in a short time and with a simple configuration. Prevents damage and enables safe charging.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a block diagram showing a schematic configuration of a charging device according to an embodiment of the present invention. In FIG. 1, 1
Is a secondary battery (assembled battery) to be charged, 2 is a power source for charging the secondary battery 1, and the power source 2 functions as a constant current power source when the secondary battery 1 is charged. Also,
The power supply 2 supplies electric power for driving a load 6 described later, and at this time, functions as a constant voltage power supply. That is, the power supply 2 is a constant-current constant-voltage power supply (so-called CVCC power supply), and normally this power supply 2 is in the form of an adapter placed outside the device.

Charging / switching 3 is for turning on / off the charging of the secondary battery 1 and for switching the power supply to the DC / DC converter 5 described later by one of the secondary battery 1 and the power supply 2 This is a circuit, and each of the built-in switches, which will be described later, is ON / OFF controlled by a control unit 4, which will be described later. 5 is DC /
It is a DC converter and receives electric power from the secondary battery 1 or the power source 2 via the charging / switching circuit 3 to generate various DC power sources for driving a load 6 described later. Reference numeral 6 is a load driven by the DC / DC converter 5. For example, when the present invention is applied to a notebook computer, the load is the CPU unit, the memory unit, the disk unit, the display unit and the like. Reference numeral 7 is a VB generation unit that generates the power supply VB used by the control unit 4.

FIG. 2 shows the charging / switching circuit 3 in FIG.
3 is a circuit diagram of a VB generator. Here, the secondary battery 1
Is a cell 10 in which five secondary batteries are connected in series.
1 and cell 102, cell 101 and cell 1
A switch 10 is connected between the plus terminals of 02 and a switch 11 is connected between the minus terminals, and the both sides of the switch are turned on so that the secondary battery 1 is connected to a battery pack of 5 parallels and 2 parallels. .

The negative terminal of the cell 102 is also connected to GND. Further, a switch 12 is connected between the negative terminal of the cell 101 and the positive terminal of the cell 102. By turning on the switch 12 and turning off the switches 10 and 11, the secondary battery 1 is a battery pack of 10 cells in series. It becomes a connection.

The output of the power supply 2 is connected to the anodes of the diode 14 and the diode 17, and the diodes 14, 17 are connected to each other.
Are connected to one ends of the switches 15 and 16, respectively. The other end of the switch 15 is the cell 101
The switch 15 controls ON / OFF of charging of the power source 2, the diode 14, the switch 15, and the secondary battery 1 through the path.

A switch 13 is connected between the connection point between the diode 17 and the switch 16 and the positive terminal of the cell 101. The switch 13 supplies electric power from the secondary battery 1 to the DC / DC converter 5. ON / OFF
Controlled. The other end of the switch 16 is connected to the DC / DC converter 5, and the power source 2
Alternatively, the power supply from the secondary battery 1 to the DC / DC converter 5 is ON / OFF controlled.

Reference numeral 71 is a regulator that outputs a constant voltage, and its output VB is supplied to the control unit 4. Power input to the regulator 71 is performed via diodes 72 and 73 whose cathodes are commonly connected. That is, the anode of the diode 72 is connected to the positive terminal of the cell 101,
The anode of the diode 73 is connected to the power supply 2 and only one of the secondary battery 1 and the power supply 2 controls the control unit 4.
The power supply VB can be supplied to. In addition, the switches 10, 11, 12, 13, 15, 16 are connected to the control unit 4
ON / OFF control is performed by, but the control terminal of each switch is omitted in FIG.

As shown in FIG. 3, the switch 15 includes transistors Tr151 and Tr152 resistors R153 and 15.
4, the emitter of the transistor Tr152 is grounded, and its collector is connected to the base of the transistor Tr151 via the resistor R153. The emitter of the transistor Tr151 is connected to the cathode of the diode 14, and the collector thereof is connected to the positive terminal of the cell 101.

The control signal S155 of the switch 15 supplied from the control unit 4 is input to the base of the transistor Tr152 via the resistor R154 and the transistor Tr15.
1 is the actual switch. That is, the control signal S15
When 5 is at high level, the transistors Tr152,
Tr151 turns on and switch 15 turns on,
When the control signal S155 is at low level, the transistors Tr152 and Tr151 are turned off and the switch 15 is turned off.

As shown in FIG. 4, the switch 16 includes transistors Tr161 and Tr162 and resistors R163 and R163.
The transistor Tr162 has an emitter which is grounded, and a collector which is connected to the base of the transistor Tr161 via the resistor R163. The emitter of the transistor Tr161 is connected to the cathode of the diode 17, and its collector is connected to the DC / DC converter 5.

The control signal S165 of the switch 16 supplied from the control unit 4 is input to the base of the transistor Tr162 via the resistor R164, and the transistor Tr16 is supplied.
1 is the actual switch. That is, the control signal S16
When 5 is high level, the transistors Tr162,
Tr161 turns on and switch 16 turns on,
When the control signal S165 is at a low level, the transistors Tr162 and Tr161 are turned off and the switch 16 is turned off.

As shown in FIG. 5, the switch 13 includes transistors Tr131 and Tr132 and resistors R133 and 13.
4, the emitter of the transistor Tr132 is grounded, and the collector thereof is connected to the base of the transistor Tr131 via the resistor R133. The emitter of the transistor Tr131 is connected to the positive terminal of the cell 101, and its collector is connected to the cathode of the diode 17.

The control signal 135 of the switch 13 supplied from the control unit 4 is supplied to the transistor T via the resistor R134.
It is input to the base of r132, and the transistor Tr132
1 is the actual switch. That is, the control signal S13
When 5 is at high level, the transistors Tr132,
Tr131 turns on and switch 13 turns on,
When the control signal S135 is at low level, the transistors Tr132 and Tr131 are turned off and the switch 13 is turned off.

As shown in FIG. 6, the switches 10, 11 and 12 are composed of relays RL 103, 111 and 121, respectively, and control signals S104,
Controlled by 112 and 122. When each control signal is high level, each relay is set and each switch is in ON state, and when each control signal is low level, each relay is reset and each switch is in OFF state.

As shown in FIG. 7, the control unit 4 has a one-chip microcomputer MCU41 as a core, and this one-chip microcomputer MCU41 is used as a work area or a ROM 413 in which programs and data are preset. RAM 41 used as a storage area
2. It has an output port group 411 for outputting control signals of various switches. Also, the output port group 411
Indicates ports P414, 415, 416, 417, 418
Has each port.

The control signal S155 for the switch 15 is output from the port P414, and the control signal S165 for the switch 16 is output from the port P415. The ports P416, 417, 418 are connected to the resistors R47, 4 respectively.
It is connected to the bases of the transistors Tr44, 45, 46 via 8,49. Transistors Tr44, 4
The collectors of 5, 46 are respectively connected to the power source VB supplied from the VB generator 7, and their emitter output signals are used as control signals S104, 112, 122 for controlling the switches 10, 11, 12, respectively. . That is, when the output ports P416, 417, 418 become high level, the transistors Tr44, 45, 46 are respectively turned on and the control signals S104, 112, 122 become high level.

The control section 4 also outputs a control signal 135 for the switch 13, which is generated by the comparator 42. That is, the comparator 42 compares the output voltage of the power supply 2 with the reference voltage output from the reference power supply 43, and when the power supply 2 outputs a voltage equal to or higher than the reference voltage, sets the control signal S135 to low level. When the output voltage of the power supply 2 is lower than the reference voltage, the control signal S135 is set to the high level. For example, when the AC power supply to the power supply 2 is cut off or the output voltage of the power supply 2 drops, the comparator 42 detects this and sets the control signal S135 to the high level. As a result, the switch S13 is turned on, and the power to the DC / DC converter 5 is supplied from the secondary battery 1.

Next, a specific operation of this embodiment will be described.

FIG. 8 shows ON of each switch in various modes.
It is a diagram showing a / OFF operation, and as shown in the figure, there are three kinds of modes of a charging mode, a power supply mode, and a secondary battery mode.

The charging mode means the DC / DC converter 5
In this mode, the power supply to the secondary battery 1 is stopped and only the secondary battery 1 is charged. In this mode, the control unit 4 turns off the switches 10 and 11 as shown in FIG.
2 is turned on so that the secondary battery 1 has a 10-cell series configuration, that is, a series-series connection, and the switch 15 is turned on, so that the power source 2, the diode 14,
Switch 15, cell 101, switch 12, cell 10
2. Make the charging current flow through the GND path. At this time, the power supply to the DC / DC converter 5 is stopped by turning off the switches 13 and 16.

As described above, since charging is performed in the state where the secondary battery (battery pack) 1 is connected in series-series, it is not necessary to reduce the charging current as in the conventional case, and charging is performed in a short time by a high current. It can be performed. Further, unlike the conventional case, it is not necessary to provide the branch current detection means, and the charging can be performed with a simple configuration.

In the power supply mode, charging of the secondary battery 1 is stopped, power supply from the secondary battery 1 to the DC / DC converter 5 is cut off, and power is supplied from the power supply 2 to the DC / DC converter 5. Mode. In this power supply mode, the switches 10 and 11 are turned on, and the switch 12 is turned off so that the secondary battery 1 has a 5-parallel 2-parallel configuration, and the switch 16 is turned on to turn on the power supply 2 and the diode 1.
7. Power is supplied to the DC / DC converter 5 through the path of the switch 16.

At this time, the charging of the secondary battery 1 is stopped by turning off the switches 13 and 15.
In addition, the switches 13 and 15 are OFF, and the secondary battery 1
Since the power supply from the power supply to the DC / DC converter 5 is cut off, the secondary battery 1 should be configured in 10 cells in series (the switch 12 is ON and the switches 10 and 11 are OFF) so that a small current can be supplied. Can also be considered. However, when the power supply 2 is cut off during operation in the power supply mode, it is necessary to instantaneously switch the power supply source to the DC / DC converter 5 to the secondary battery 1. On the other hand, the DC / DC converter 5 needs to supply a large current to the load 6. Therefore, as described above, the secondary battery 1 is preliminarily set to the 5-parallel 2-para configuration capable of supplying a large current, that is, the discharge mode, and the power supply source to the DC / DC converter 5 is instantly recharged. It is preferable to be able to switch to the battery 1.

The secondary battery mode is a mode in which charging of the secondary battery 1 is stopped and no power is supplied from the power source 2 (for example,
This is a mode in which power is supplied from the secondary battery 1 to the DC / DC converter 5 when the AC power is not supplied to the power supply 2 or when the power supply 2 itself is not present. In this secondary battery mode, the switches 10 and 11 are turned on and the switch 12 is turned on.
By performing FF, the secondary battery 1 has a 5-parallel 2-para configuration,
The switches 13 and 16 are turned on to supply electric power to the DC / DC converter 5 through the path of the secondary battery 1, the switch 13 and the switch 16. At this time, the switch 15 is turned off.

FIG. 9 is a timing chart showing the transition of each control signal when the above-mentioned modes are transited by the control of the control unit 4. Basically, only the control signal corresponding to ON / OFF of each switch shown in FIG. 8 transits. However, in the portion indicated by A and B in FIG. 9, that is, when the charging mode is switched to the power supply mode. And, since it is necessary to be careful when shifting from the power supply mode to the charging mode, this part will be described in detail.

In the portion A for shifting from the charging mode to the power supply mode, first, the control signal S155 is set to the low level to turn off the switch 15 to stop the charging. Next, the control signal S122 is changed from high level to low level to turn the switch 12 from ON to OFF, and the control signals S104 and S112 are changed from low level to high level to turn the switches 10 and 11 from OFF to ON. Secondary battery 1 with 10-cell series configuration
Is converted to a 5 para 2 para configuration.

At this time, it should be noted that the switch 1
This is to turn off the switch 12 before turning 0 and 11 on. If this is reversed, cell 101 or cell 1
This is because the positive terminal and the negative terminal of 02 are short-circuited. Therefore, as indicated by A in FIG. 9, the control signals S155, S122, S104 and S112 are changed in this order. After that, the control signal S165 is set to the high level to turn on the switch 16 and shift to the power supply mode.

As described above, the connection state is switched by the cell 1
01 or the cell 102 while avoiding a short circuit between the positive terminal and the negative terminal of the cell 102, it is possible to prevent the secondary battery (assembled battery) 1 from being destroyed and to charge the battery safely.

In the portion B for shifting from the power supply mode to the charging mode, first, the control signal S165 is set to the low level to turn off the switch 16 to stop the power supply to the DC / DC converter 5. Next, the control signal S1
04 and 112 are changed from the high level to the low level, the switches 10 and 11 are changed from ON to OFF, and the control signal S122
Switch from low level to high level and switch 12 to OF
By switching from F to ON, the configuration of the secondary battery 1 is converted from 5 direct 2 para to 10 cell serial configuration.

Also in this case, since the cells of the secondary battery 1 are not short-circuited, as shown in FIG.
165, S104 and S112, S122 are controlled in this order. After that, the control signal S165 is set to the low level to turn off the switch 16 and shift to the charging mode.

[0047]

As described above, according to the present invention,
When charging an assembled battery used as a power source in a series-parallel connection state in which a plurality of battery groups consisting of a plurality of series-connected secondary batteries are connected in parallel, it is switched to the series-series connection state. , Without reducing the charging current
The high current makes it possible to charge the battery in a short time.

Further, unlike the conventional case, it is not necessary to provide branch current detecting means, and charging can be performed with a simple structure.

Since the connection state is switched while avoiding a short circuit between the positive terminal and the negative terminal of the battery group,
It is possible to prevent the battery pack from being destroyed and safely charge the battery pack.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a charging device according to an embodiment of the present invention.

FIG. 2 is a circuit diagram showing configurations of a charging / switching circuit and a VB generation unit.

FIG. 3 is a circuit diagram showing a configuration of a switch 15.

FIG. 4 is a circuit diagram showing a configuration of a switch 16.

5 is a circuit diagram showing a configuration of a switch 13. FIG.

FIG. 6 is a circuit diagram showing a configuration of switches 10, 11 and 12.

FIG. 7 is a diagram showing a configuration of a control unit.

FIG. 8: ON / OFF of each switch in various modes
It is explanatory drawing for demonstrating operation.

FIG. 9 is a timing chart showing transition of each control signal when transitioning between modes.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Secondary battery 2 ... Power supply 3 ... Charging / switching circuit 4 ... Control part 5 ... DC / DC converter 7 ... VB generation part 10, 11, 12 ... Switch 101, 102 ... Cell 41 ... MCU 411 ... Output port group 412 … RAM 413… ROM

Claims (4)

[Claims] 1. A charging device for charging an assembled battery used as a power source in a series-parallel connection state in which a plurality of battery groups each composed of a plurality of series-connected secondary batteries are connected in parallel. A power supply unit that supplies a charging current to the battery group, a series-parallel connection configuration in which a plurality of groups of the battery groups are connected in parallel, and a series-series connection configuration in which a plurality of groups of the battery groups are connected in series. Switching means for switching, and control means for controlling the switching operation of the switching means so as to make the configuration of the assembled battery a series-series connection configuration when the charging current is supplied from the power source unit to the assembled battery for charging. And a charging device comprising: 2. The control means adopts a series-series connection configuration as a configuration of the assembled battery when the charging current is supplied from the power source unit to the assembled battery to perform charging, and the assembly means when the assembled battery is used as a power source. The charging device according to claim 1, wherein the switching operation of the switching means is controlled so that the battery has a series-parallel connection configuration. 3. The control means controls the switching operation of the switching means so as to make the configuration of the assembled battery into a series-series connection configuration while avoiding a short circuit between the positive terminal and the negative terminal of the battery group. The charging device according to claim 1, wherein: 4. The switching means for controlling the battery pack to have a series-series connection configuration or a series-parallel connection configuration while avoiding a short circuit between the positive terminal and the negative terminal of the battery group. The charging device according to claim 2, wherein the switching operation is controlled.