JP2005317283A - Batter pack and charging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery pack which is charged or not charged depending on the combination of the battery pack and a charging device, and also to provide a charging device corresponding to the battery pack. <P>SOLUTION: The battery pack 1 is composed of a battery 1a, a pseudo-high temperature element 1b, a thermistor 1c, and a battery type judging element 1d. A charge allowing/not allowing means is constituted by the pseudo-high temperature element 1b and the thermistor 1c. The pseudo-high temperature element 1b indicates that the temperature of the battery 1a exceeds a prescribed temperature. When the battery is erroneously connected to a charging device not provided with a proper charge control method, it is judged so that the temperature of battery 1a is higher than the prescribed temperature by an information from the pseudo-high temperature element 1b, and charging is not performed. When the battery pack 1 is connected to a charger 200, the charger 200 judges whether the battery pack 1 is equipped with the thermistor 1c. A second battery temperature detection circuit 100 detects the temperature of the battery 1a through the thermistor 1c, and a charging is performed by switching a constant current control and constant voltage control in accordance with the temperature and voltage of the battery or the like. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a battery pack that is charged or not charged depending on a combination of a battery pack and a charging device, and a charging device corresponding to the battery pack.

  There are various types of secondary batteries (hereinafter referred to as “batteries”) that are charged by a charging device, and they are properly used according to their intended use. For example, a battery used for a power tool such as a cordless driver is preferably a high power battery that can be charged in a short time from the viewpoint of work efficiency. Therefore, nickel cadmium batteries (hereinafter referred to as NiCad batteries) and nickel metal hydride batteries that can be discharged with a large current and that can be charged in a short time are widely used as power tool batteries. As the charging method, constant current charging capable of high-speed charging is adopted.

  On the other hand, it has not been used as a battery for power tools in the past, but due to its high output density, it is expected to use a lithium ion battery (hereinafter referred to as a lithium battery) that is expected to further increase its capacity and weight. Has been. However, when a voltage exceeding a predetermined value is applied to a lithium battery, there is a risk of ignition in the worst case, and handling is very difficult. For this reason, the lithium battery needs to be charged at a constant current in the initial charge, and should be charged at a constant voltage when the battery voltage reaches a predetermined value.

Patent Document 1 proposes a charging method that can charge a nickel-cadmium battery, a lithium battery, or the like with a single charging device that does not include a constant voltage charging circuit. In this charging method, temperature rise pattern data for each battery type is carried in advance, the type of battery is determined based on that data, and if constant voltage charging is required, a constant current circuit is used to Constant voltage charging is realized. Thus, in the charging method of Patent Document 1, the battery pack and the charging device cooperate to determine the charging method.
JP 2002-191135 A (page 3-8, FIG. 1)

  However, in the above charging method, charging must be performed between the corresponding battery pack and the charging device. Therefore, when the battery pack is connected to a charging device that does not have a battery type discrimination function, the battery pack may be charged by a charging method that does not correspond to the type. For example, when a battery pack that requires constant current charging and constant voltage charging, such as a lithium battery, is mistakenly connected to a conventional charging device that supports only constant current charging, constant current charging is performed. In such a case, there is a risk of causing danger such as battery ignition due to overcharge.

  Therefore, an object of the present invention is to provide a battery pack that is charged or not charged depending on the combination of the battery pack and the charging device, and a charging device corresponding to the battery pack.

  In order to achieve the above object, the battery pack according to claim 1 includes a battery charged by the charging device, and charging permission / non-permission information providing means for causing the charging device to determine whether charging is permitted or not. It is characterized by that.

  According to such a configuration, the battery pack itself has means for providing the charging device with information indicating permission / non-permission of charging.

  The invention described in claim 2 is the invention described in claim 1, wherein the charging permission / non-permission information providing means is connected to a charging device capable of performing constant current charging and constant voltage charging. Is characterized in that the charging device determines permission of charging, and when connected to a charging device that performs only constant current charging, the charging device determines whether charging is not permitted.

  According to such a configuration, when the battery pack is connected to a charging device capable of performing constant current charging and constant voltage charging, the battery pack provides charging permission information to the charging device and performs only constant current charging. When connected to the charging device, the charging device is provided with information indicating that charging is not permitted.

  Further, in the invention described in claim 3, in the invention described in claim 1, the charging permission / non-permission information providing means includes a pseudo high temperature element indicating that the battery temperature of the battery is equal to or higher than a predetermined value, a battery temperature It has the temperature information element which shows.

  According to such a configuration, the battery pack provides charging permission / non-permission information to the charging device by the pseudo high temperature element and the temperature information element.

  The invention according to claim 4 is the invention according to claim 1, characterized in that the battery is a lithium battery.

  According to such a configuration, the battery pack having the lithium battery provides the charging device with permission / denial information on charging.

  The invention described in claim 5 is characterized in that, in the invention described in claim 1, it is used for a power tool.

  According to such a configuration, the battery pack for the electric tool causes the charging device to determine whether charging is permitted or not.

  The charging device according to claim 6 is a charging circuit that supplies a charging current to a battery constituting the battery pack, a first temperature detecting means that is connected to the battery pack and detects the battery temperature, and a second battery temperature detection. And when the second battery temperature detecting means is connected to the battery pack, it is determined whether or not the battery temperature indicates a predetermined value or more, and the battery temperature is determined to be less than the predetermined value. When charging is started and it is determined that the battery temperature is equal to or higher than a predetermined value, charging is not started, the second battery temperature detecting means is not connected to the battery pack, and only the first battery temperature detecting means is connected to the battery pack. Sometimes, it is determined whether or not the battery temperature is greater than or equal to a predetermined value, and charging is started when it is determined that the battery temperature is lower than the predetermined value, and charging is performed when it is determined that the battery temperature is higher than or equal to the predetermined value. Don't start It is characterized by a door.

  According to such a configuration, when the battery pack is connected to the second battery temperature detection means, the charging device starts charging based on the battery temperature detected by the second battery temperature detection means, When the battery pack is connected only to the battery temperature detecting means, charging is started based on the battery temperature detected by the first battery temperature detecting means.

  According to a seventh aspect of the present invention, there is provided a charging device according to the sixth aspect of the present invention, wherein the constant current control means for controlling the charging current of the charging circuit to a predetermined value and the constant voltage for controlling the charging voltage of the charging circuit to a predetermined value. Voltage control means, and when the second battery temperature detection means is connected to the battery pack, it is determined whether or not the battery temperature indicates a predetermined value or more, and the battery temperature is less than the predetermined value. If it is determined that there is, the constant current control means and the constant voltage control means perform constant current charging and constant voltage charging according to the state of charge of the battery, the second battery temperature detection means is not connected to the battery pack, and the first battery temperature detection When only the means is connected to the battery pack, the first battery temperature detecting means determines whether or not the battery temperature indicates a predetermined value or more, and if the battery temperature is determined to be less than the predetermined value, the constant current control By means It is characterized by performing current charging.

  According to such a configuration, when the battery pack is connected to the second battery temperature detecting means, the charging device performs constant current charging and constant voltage charging, and the battery pack is provided only to the first battery temperature detecting means. When connected, constant current charging is performed.

  According to the battery pack described in claim 1 of the present invention, since the battery pack includes charging permission / non-permission information providing means, the charging control method of the connected charging device does not support the battery pack. The battery is not charged, and the risk of ignition due to overcharging and the deterioration of the battery pack can be prevented.

  According to the battery pack of claim 2 of the present invention, the battery pack is not charged when the battery pack of the present invention is connected to a charging device that does not have a constant current charging and constant voltage charging control system. Therefore, it is possible to prevent the risk of ignition due to overcharge and the deterioration of the battery pack.

  According to the battery pack of the third aspect of the present invention, since the charging device is provided with charging permission / non-permission information only by the temperature information of the pseudo high temperature element and the temperature information element, the temperature detection of the conventional charging device is performed. Means can be used.

  According to the battery pack described in claim 4 of the present invention, since the battery pack made of a lithium battery includes the charging permission / non-permission information providing means, the charging control method of the connected charging device corresponds to the battery pack. If not, the battery is not charged, and the risk of ignition due to overcharging and the deterioration of the battery pack can be prevented.

  According to the battery pack according to claim 5 of the present invention, since the battery pack includes charging permission / non-permission information providing means, the charging control method of the connected charging device does not support the battery pack. The battery is not charged, and the risk of ignition due to overcharging and the deterioration of the battery pack can be prevented.

  According to the charging device of the sixth aspect of the present invention, it is determined whether or not to start charging based on a simple condition of the connection state of the first battery temperature detecting means and the second battery temperature detecting means with the battery pack. can do.

  According to the charging device of the seventh aspect of the present invention, the charging control method can be determined by a simple condition of the connection state of the first battery temperature detecting means and the second battery temperature detecting means with the battery pack. .

  Hereinafter, a battery pack and a charging device according to a first embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the battery pack 1 according to the present embodiment includes a plurality of batteries 1a, a pseudo high temperature element 1b, a thermistor 1c, a battery type discrimination element 1d, terminals 1e, 1f, 1g, 1h, and 1i. Yes.

  The battery 1a is a lithium battery that may ignite due to excessive battery temperature when charged only by constant current charging. A terminal 1h is connected to the positive electrode side of the battery 1a, and a terminal 1i is connected to the negative electrode side. On the negative electrode side, a pseudo high temperature element 1b, a thermistor 1c, and a battery type discrimination element 1d are connected in parallel. The pseudo high temperature element 1b is an element indicating pseudo high temperature information for determining that the temperature of the battery 1a is high, and includes, for example, a resistor. The thermistor 1c is a temperature-sensitive element that is a temperature information element that contacts the battery 1a and indicates battery temperature information corresponding to the battery temperature. The pseudo high temperature element 1b and the thermistor 1c constitute charging permission / non-permission information providing means for providing charging permission / non-permission information to the charging device. The battery type discriminating element 1d is an element that shows information according to the type of the battery 1a.

  Terminals 1e, 1f, and 1g are connected to the other ends of the pseudo high temperature element 1b, the thermistor 1c, and the battery type discrimination element 1d, respectively. Terminals 1e, 1f, and 1g are connection terminals for providing information from the pseudo high temperature element 1b, the thermistor 1c, and the battery type discrimination element 1d to the charging device, respectively. The positions of the terminals 1e, 1f, and 1g in the battery pack 1 are defined as a first position, a second position, and a third position, respectively.

  Hereinafter, the case where the battery pack 1 is connected to a charging device that does not support constant current charging and constant voltage charging will be described. FIG. 2 is a block diagram when the battery pack 1 is connected to the charging device 2 that does not support constant current charging and constant voltage charging. The charging device 2 is a conventional charging device for charging a nickel-cadmium battery, a nickel-metal hydride battery, or the like that can perform only constant current charging.

  As shown in FIG. 2, the battery pack 1 is detachably connected to the charging device 2. The charging device 2 includes a resistor 3 as charging current detection means, a photocoupler 4 as charging control signal transmission means, a photocoupler 5 as charging current signal transmission means, a charging current setting circuit 7 as charging current setting means, and a first rectifying and smoothing circuit. 10, switch circuit 20, second rectifying / smoothing circuit 30, battery voltage detection circuit 40 as battery voltage detection means, microcomputer 50, charge current control circuit 60 as charge current control means, constant voltage power supply 80, first battery temperature detection means A first battery temperature detection circuit 90 is provided, and a battery type determination circuit 110 as battery type determination means. Hereinafter, the configuration of the charging device 2 will be described in detail.

  The resistor 3 detects a charging current for charging the battery pack 1 and inputs the result to an inverting input terminal of an operational amplifier 61 described later. The photocoupler 4 is a charge control signal transmission circuit, and transmits a signal for controlling start and stop of charging to the PWM control IC 23 based on an input signal from the output port 52. If the signal input from the first battery temperature detection circuit 90 to the microcomputer 50 indicates a temperature that cannot be charged at high temperature, the microcomputer 50 sends a signal for controlling the stop of charging to the PWM control IC 23 via the photocoupler 4. introduce.

  The photocoupler 5 is a charging current signal transmission circuit. An input signal from the charging current control circuit 60 is fed back to the PWM control IC 23 via the photocoupler 5.

  The charging current setting circuit 7 receives a signal corresponding to the type of the battery 1 a from the output port 52. Based on the signal, a predetermined charging current value is set by changing a voltage value applied to an inverting input terminal of an operational amplifier 62 described later.

  The AC power supply 9 is a commercial power supply. The alternating current output from the alternating current power source 9 is input to the first rectifying and smoothing circuit 10. The first rectifying / smoothing circuit 10 includes a full-wave rectifying circuit 11 and a smoothing capacitor 12.

  The switch circuit 20 includes a high-frequency transformer 21, a MOSFET 22, and a PWM control IC 23. The MOSFET 22 is turned on / off in response to a signal from the PWM control IC 23. As a result, the direct current output from the first rectifying and smoothing circuit 10 becomes alternating current. This alternating current is transformed by the high frequency transformer 21.

  The rectifying / smoothing circuit 30 includes diodes 31 and 32, a choke coil 33, and a smoothing capacitor 34. The alternating current output from the high-frequency transformer 21 is rectified by the diodes 31 and 32 and smoothed by the choke coil 33 and the smoothing capacitor 34.

  The battery voltage detection circuit 40 includes resistors 41 and 42. The terminal voltage of the battery pack 1 is divided and detected by the resistors 41 and 42, and the detected battery voltage is output to the microcomputer 50.

  The microcomputer 50 includes an A / D converter 51, an output port 52, a reset input port 53, a CPU 54, a timer 55, a RAM 56, and a ROM 57, which are connected to each other via an internal bus. The A / D converter 51 uses the analog voltage information output from the first battery temperature detection circuit 90 and the battery type determination circuit 110 as a digital signal. The reset input port 53 sets the microcomputer 50 in an initial state when a reset input signal is input from a reset IC 85 described later. The ROM 57 stores a voltage for charging the nickel-cadmium battery and the nickel-metal hydride battery. The CPU 54 outputs the result determined based on the input signal from the above-mentioned members connected to the bus to the output port 52.

  The charging current control circuit 60 includes operational amplifiers 61 and 62 and resistors 63 to 66. The charging current control circuit 60 outputs a result of comparing the charging current detected by the resistor 3 with the set charging current set by the charging current setting circuit 7.

  The constant voltage power supply 80 includes a power transformer 81, a full-wave rectifier circuit 82, a three-terminal regulator 83, a smoothing capacitor 84, and a reset IC 85. The constant voltage power supply 80 is a power supply for the microcomputer 50, the charging current control circuit 60, and the like. The reset IC 85 outputs a reset signal to the reset input port 53 when the power is turned on.

  The first battery temperature detection circuit 90 includes a 5V power source and resistors 91 and 92. The 1st battery temperature detection circuit 90 is arrange | positioned in the position which can be connected with the 1st position of the battery pack 1, and is connected with the pseudo high temperature element 1b of the battery pack 1 by the connection terminal 1e. The first battery temperature detection circuit 90 detects the temperature of the battery 1a from the voltage divided by the first battery temperature detection circuit 90 and the pseudo high temperature element 1b, and outputs the result to the microcomputer 50 as voltage information.

  The battery type discriminating circuit 110 includes a 5V power source and resistors 111 and 112. The battery type discriminating circuit 110 is disposed at a position connectable to the third position of the battery pack 1, and is connected to the battery type discriminating element 1d of the battery pack 1 through the connection terminal 1g. The battery type discriminating circuit 110 discriminates whether the type of the battery 1a is a nickel-cadmium battery or a nickel metal hydride battery from the voltage divided by the battery type discriminating circuit 110 and the battery type discriminating element 1d. Output as.

  When the battery pack 1 is connected to the charging device 2 as described above, the first temperature detection circuit 90 receives information indicating that the battery 1a is equal to or higher than a predetermined temperature by the pseudo high temperature element 1b. The first temperature detection circuit 90 outputs the voltage divided by the first battery temperature detection circuit 90 and the pseudo high temperature element 1b to the microcomputer 50 as voltage information. At this time, since the microcomputer 50 determines that the temperature of the battery 1a is equal to or higher than a predetermined temperature, the battery pack 1 is not charged.

  A case where a battery pack 130 capable of constant current charging, such as a nickel-cadmium battery or a nickel hydride battery, is connected to the charging device 2 will be described with reference to FIG. FIG. 3 is a block diagram when the battery pack 130 is connected to the charging device 2 that performs only constant current charging.

  The battery pack 130 includes a battery 130a, a thermistor 130b, and a battery type discrimination element 130d. The battery 130a can be charged only at a constant current, such as a nickel-cadmium battery or a nickel metal hydride battery, and a terminal 130h (not shown) is connected to the positive electrode side, and a terminal 130i (not shown) is connected to the negative electrode side. Yes. A thermistor 130b and a battery type discriminating element 130d are connected in parallel to the negative electrode side. The thermistor 130b is a temperature sensitive element that is a temperature information element that contacts the battery 130a and indicates battery temperature information corresponding to the battery temperature. The battery type identification element 130d is an element that indicates information according to the type of the battery 130a. The terminal 130 h is disposed at the first position in the battery pack 1, and the terminal 130 i is disposed at the third position in the battery pack 1. Therefore, when connected to the charging device 2, the thermistor 130 b is connected to the first battery temperature detection circuit 90, and the battery type determination element 130 d is connected to the battery type determination circuit 110.

  When the battery pack 130 is connected to the charging device 2, the state of charge of the battery 130a detected by the battery voltage detection circuit 40, the battery temperature of the battery 130a detected by the first battery temperature detection circuit 90, Based on the battery type of the battery 130 a determined by the battery type determination circuit 110, the microcomputer 50 sends a current signal to be charged to the charging current control circuit 60. The charging current control circuit 60 compares the charging current detected by the resistor 3 with the charging current value set by the charging current setting circuit 7 and inputs the result to the PWM control IC 23. The PWM control IC 23 turns on and off the switch circuit 20 to keep the charging current for charging the battery 130a at a predetermined value. As described above, the battery pack 130 is charged with the predetermined charging current corresponding to the battery type.

  Next, the operation of the charging device 2 when the battery pack 1 or the battery pack 130 is connected will be described using the flowchart of FIG. First, it is determined whether or not a battery pack is connected to the charging device 2 (S1). When it is determined that the battery pack is connected (S1: YES), the battery type is determined by the battery type determination element of the battery pack (S2). When it is determined that the battery pack is not connected (S1: NO), monitoring of the connection state of the battery pack is continued as it is.

  If the battery determined in S2 is a nickel-cadmium battery (S3: YES), whether or not the battery temperature T1 detected by the first battery temperature detection circuit 90 is lower than a predetermined temperature A that is high temperature and cannot be charged. Is discriminated (S4). When the battery temperature T1 is lower than the predetermined temperature A (S4: YES), it is determined that the battery is in a chargeable state, and constant current (Ic1) charging for the nickel-cadmium battery is started (S5). When the battery temperature T1 is higher than the predetermined temperature A (S4: NO), it is determined that the battery is not in a chargeable state, and the battery temperature T1 is continuously monitored in S4. Here, the monitoring of the battery temperature T1 may be limited by time or the like, and charging may be stopped when a predetermined time or more has elapsed.

  Next, it is determined whether or not the battery is fully charged by the constant current charging started in S5 (S6). If it is determined that the battery is fully charged (S6: YES), charging is stopped (S7). If it is determined that the battery is not fully charged (S6: NO), the battery is continuously monitored for full charge.

  Finally, it is determined whether or not the battery pack is detached from the charging device 2 (S8). If it is determined that the battery pack has been detached (S8: YES), the process returns to S1 and monitoring of battery pack connection is started again. At this time, the microcomputer 50 resets the state of the output port 52 and the data in the RAM 56. When it is determined that the battery pack has not been detached (S8: NO), the battery pack removal is continuously monitored.

  On the other hand, when the battery determined in S2 is not a nickel-cadmium battery (S3: NO), subsequently, the battery temperature T1 detected by the first battery temperature detection circuit 90 is higher than a predetermined temperature A at which charging is not possible. It is determined whether or not it is low (S9). When the battery temperature T1 is lower than the predetermined temperature A (S9: YES), it is determined that the battery is in a chargeable state, and at the same time, it is determined that the battery is a nickel metal hydride battery (S10). And the constant current (Ic2) charge for nickel hydride batteries is started (S11).

  When the battery temperature T1 is higher than the predetermined temperature A (S9: NO), it is determined that the battery is not in a chargeable state, and the battery temperature T1 is continuously monitored. Here, when the connected battery is a lithium battery, the pseudo high temperature element 1b serving as charging permission / non-permission information providing means for causing the charging device 2 to determine that the battery is hot is connected to the first battery temperature detection circuit 90. Since it is connected, it is determined that the temperature T1 is always higher than the predetermined temperature A. In this case as well, the monitoring of the battery temperature T1 may be limited by time or the like, and charging may be stopped when a predetermined time or more has elapsed.

  Next, it is determined whether or not the battery is fully charged by the constant current charging started in S11 (S12). If it is determined that the battery is fully charged (S12: YES), charging is stopped (S13). If it is determined that the battery is not fully charged (S12: NO), the battery is continuously monitored for full charge.

  Finally, it is determined whether or not the battery pack is detached from the charging device 2 (S14). When the battery pack is detached (S14: YES), the process returns to S1 and monitoring of the battery pack connection is started again. When the battery pack is not detached (S14: NO), the battery pack removal is continuously monitored as it is.

  As described above, since the battery pack 1 according to the present embodiment has the charging permission / non-permission information providing means including the pseudo high temperature element 1b and the thermistor 1c, constant current charging and constant voltage charging cannot be performed. Even if connected to the charging device 2 by mistake, the battery 1a such as a lithium battery is not charged. Thereby, the danger and deterioration by ignition of the battery 1a can be prevented.

  Next, the charging device 200 that charges the battery pack 1 according to the present embodiment will be described. FIG. 5 is a block diagram when battery pack 1 is connected to charging device 200 according to one embodiment of the present invention. The charging device 200 is a charging device that can appropriately perform constant current charging and constant voltage charging depending on the state or type of charge of the battery. Therefore, the charging device 200 can charge a nickel-cadmium battery or a nickel-metal hydride battery, and can charge a battery, such as a lithium battery, which has a risk of ignition or the like due to excessive battery temperature in constant current charging.

  As shown in FIG. 5, the battery pack 1 is detachably connected to the charging device 200. The charging device 200 has a configuration similar to that of the charging device 2, and includes a switching circuit 6 as switching means, a charging voltage setting circuit 8 as charging voltage setting means, a charging voltage control circuit 70 as charging voltage control means, and a second battery temperature detection. A second battery temperature detection circuit 100 as means is further provided. Hereinafter, the configuration of the charging device 200 will be described in comparison with the charging device 2.

  The switching circuit 6 is connected to the output side of the charging current control circuit 60 and the charging voltage control circuit 70. The switching circuit 6 switches to either the charging current control circuit 60 that performs constant current control or the charging voltage control circuit 70 that performs constant voltage control according to the signal output from the output port 52.

  The charging voltage setting circuit 8 receives a signal corresponding to the type of the battery 1 a from the output port 52. Based on the signal, a charging voltage is set by changing a voltage value applied to an inverting input terminal of an operational amplifier 72 described later.

  The charging voltage control circuit 70 includes operational amplifiers 71 and 72 and resistors 73 to 76. The charging voltage control circuit 70 outputs a result of comparing the voltage output from the rectifying and smoothing circuit 30 with the charging voltage set by the charging voltage setting circuit 8.

    The first battery temperature detection circuit 90 is located at a position connectable to the first position of the battery pack 1, and the second temperature detection circuit 100 is located at a position connectable to the second position of the battery pack 1. Are arranged at positions connectable to the third position of the battery pack 1, respectively. Accordingly, when connected to the battery pack 1, the first battery temperature detection circuit 90 is connected to the pseudo high temperature element 1b, the second battery temperature detection circuit 100 is connected to the thermistor 1c, and the battery type determination circuit 110 is connected to the battery type determination element 1d. Is done.

  The second battery temperature detection circuit 100 includes a 5V power source and resistors 101 and 102. The second battery temperature detection circuit 100 is connected to the thermistor 1c of the battery pack 1 through the connection terminal 1f. The second battery temperature detection circuit 100 detects the temperature of the battery 1a from the voltage divided by the second battery temperature detection circuit 100 and the thermistor 1c, and outputs the result to the microcomputer 50 as voltage information.

  The battery type discrimination circuit 110 is connected to the battery type discrimination element 1d of the battery pack 1 through the connection terminal 1g. The battery type discriminating circuit 110 discriminates whether the type of the battery 1a is a nickel-cadmium battery, a nickel metal hydride battery or a lithium battery from the voltage divided by the battery type discriminating circuit 110 and the battery type discriminating element 1d. Output as voltage information.

  The ROM 57 of the microcomputer 50 stores a voltage for charging the lithium battery.

  When the battery pack 1 is connected to the charging device 200, the battery voltage of the battery 1a detected by the battery voltage detection circuit 40, the battery temperature of the battery 1a detected by the second battery temperature detection circuit 100, Based on the battery type of the battery 1 a determined by the battery type determination circuit 110, the microcomputer 50 sends a switching signal to the switching circuit 6.

  The switching circuit 6 switches to either the charging current control circuit 60 or the charging voltage control circuit 70 according to the input signal. The microcomputer 50 sends a current signal or a voltage signal to be charged to the charging current control circuit 60 or the charging voltage control circuit 70.

  When performing constant current charging, the charging current control circuit 60 compares the charging current detected by the resistor 3 with the current set by the charging current setting circuit 7 and inputs the result to the PWM control IC 23. The PWM control IC 23 keeps the charging current at a predetermined value by turning the switch circuit 20 on and off.

  When performing constant voltage charging, the charging voltage control circuit 70 outputs a result of comparing the voltage output from the rectifying and smoothing circuit 30 with the charging voltage set by the charging voltage setting circuit 8. The result is input to the switch circuit 20 to keep the charging voltage at a predetermined value.

  The battery pack 1 is charged at a constant current by the charging device 200 until the battery voltage reaches a predetermined value, and then charged at a constant voltage.

  Next, a case where a battery pack 130 made of a nickel-cadmium battery or a nickel metal hydride battery is connected to the charging apparatus 200 according to the present embodiment will be described with reference to FIG.

  FIG. 6 is a block diagram in which battery pack 130 is connected to charging device 200 according to the present embodiment. The description of the same configuration and operation as when the battery pack 1 is connected to the charging device 200 is omitted.

  As shown in FIG. 6, in this case, the first battery temperature detection circuit 90 disposed at a position connectable to the first position of the battery pack 130, and the battery pack 130 disposed at the first position. The thermistor 130b is connected by a connection terminal (not shown). The first battery temperature detection circuit 90 detects the temperature of the battery 130a from the voltage divided by the first battery temperature detection circuit 90 and the thermistor 130b, and outputs the result to the microcomputer 50 as voltage information.

  On the other hand, since the battery pack 130 has no element at the second position, the information from the battery pack 130 is provided to the second battery temperature detection circuit 100 disposed at the second position of the battery pack 130. Not. The second battery temperature detection circuit 100 outputs the voltage divided by the resistors 101 and 102 to the microcomputer 50 as voltage information.

  The battery type discrimination circuit 110 arranged at a position connectable to the third position of the battery pack 130 and the battery type discrimination element 130d of the battery pack 130 are connected by a connection terminal (not shown). The battery type discriminating circuit 110 discriminates whether the type of the battery 130a is a nickel-cadmium battery, a nickel metal hydride battery or a lithium battery from the voltage divided by the battery type discriminating circuit 110 and the battery type discriminating element 130d, and the result is the microcomputer 50. Output as voltage information.

  When the battery pack 130 is connected to the charging device 200, the battery voltage of the battery 130a detected by the battery voltage detection circuit 40, the battery temperature of the battery 130a detected by the first battery temperature detection circuit 90, Based on the battery type of the battery 130 a determined by the battery type determination circuit 110, the microcomputer 50 sends a switching signal to the switching circuit 6.

  Since the battery 130a is a nickel-cadmium battery or a nickel metal hydride battery, the switching circuit 6 switches to the charging current control circuit 60 in accordance with the input signal. Further, the microcomputer 50 sends a current signal to be charged to the charging current control circuit 60. The charging current control circuit 60 compares the charging current detected by the resistor 3 with the current set by the charging current setting circuit 7 and inputs the result to the PWM control IC 23. The PWM control IC 23 turns on and off the switch circuit 20 to keep the charging current for charging the battery 130a at a predetermined value.

  In this way, the battery pack 130 is charged with a constant current by the charging device 200.

  Next, the operation of the charging device 200 when the battery pack 1 or the battery pack 130 is connected will be described using the flowchart of FIG. First, it is determined whether or not a battery pack is connected to the charging device 200 (S21). When it is determined that the battery pack is connected (S21: YES), it is determined whether or not the battery pack has the thermistor 1c as charging permission / non-permission information providing means (S22). When it is determined that the battery pack is not connected (S21: NO), monitoring of the connection state of the battery pack is continued as it is.

  If it is determined that the battery pack has the thermistor 1c (S22: YES), it is determined that the connected battery is a lithium battery (S23). If it is determined that the battery pack does not have the thermistor 1c (S22: NO), it is determined that the connected battery is a nickel-cadmium battery or a nickel metal hydride battery (S23).

  If it is determined in S23 that the connected battery is a lithium battery, the battery type is confirmed by the battery type determination element (S24). Subsequently, it is determined whether or not the battery temperature T2 detected by the second battery temperature detection circuit 100 is lower than a predetermined temperature A ′ that is high and cannot be charged (S25). If the battery temperature T2 is lower than the predetermined temperature A '(S25: YES), it is determined that the battery is in a chargeable state, and constant current (Ic1) charging for the lithium battery is started (S26). If the battery temperature T2 is higher than the predetermined temperature A '(S25: NO), it is determined that the battery is not in a chargeable state, and the battery temperature T2 is continuously monitored in S25.

  Next, it is determined whether or not the battery voltage V has become equal to or higher than the appropriate voltage Vc by the constant current charging started in S26 (S27). When the battery voltage V is equal to or higher than Vc (S27: YES), switching from constant current (Ic1) charging to constant voltage (Vc) charging is performed (S28). Subsequently, it is determined whether or not the battery is fully charged by the constant voltage (Vc) charging started in S28 (S29). If it is determined that the battery is fully charged (S29: YES), charging is stopped (S31). If it is determined that the battery is not fully charged (S29: NO), monitoring of the full charge is continued.

  On the other hand, if it is determined in S27 that the battery voltage V is not equal to or higher than Vc (S27: NO), it is determined whether or not the battery is fully charged (S30). If it is determined that the battery is fully charged (S30: YES), charging is stopped (S31). If it is determined that the battery is not fully charged (S30: NO), the process returns to S27, and continues monitoring whether or not the battery voltage V is equal to or higher than the predetermined voltage Vc.

  Finally, it is determined whether or not the battery pack is detached from the charging device 200 (S32). When it is determined that the battery pack has been detached from the charging device 200 (S32: YES), the process returns to S21, and monitoring of the connection of the battery pack is started again. At this time, the microcomputer 50 resets the state of the output port 52 and the data in the RAM 56. When it is determined that the battery pack is not detached from the charging device 200 (S32: NO), the battery pack removal is continuously monitored.

  As described above, when connected to the charging device 200 that can perform only constant current charging or can perform constant current and constant voltage charging, the nickel-cadmium battery, the nickel-metal hydride battery, and the lithium battery are respectively appropriate. Charged in mode. Thereby, deterioration and ignition of a battery can be prevented.

  As described above in detail, according to the battery pack 1 of the present embodiment, even if the battery pack 1 according to the present embodiment is erroneously connected to the charging device 2 that does not support constant current charging and constant voltage charging, the battery 1a is above a predetermined temperature. Therefore, it is not charged.

  Moreover, according to the charging device 200 according to the present embodiment, it is determined whether or not the connected battery pack includes the thermistor 1c as charging permission / non-permission information providing means. Since constant voltage charging is performed when the value exceeds a predetermined value, it is possible to prevent deterioration of the battery or ignition during charging.

  When the battery pack 130 capable of only constant current charging is connected to the charging device 200, the first temperature detection circuit 90 detects the temperature of the battery 130a by the thermistor 130b, and the battery type determination element 110 is the battery type determination element 130d. Since the type of the battery is determined by the constant current charging, constant current charging with an appropriate charging current can be performed.

  The preferred embodiments of the battery pack and the charging device according to the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to the above-described embodiments. Those skilled in the art can make various modifications and improvements within the scope of the technical idea described in the claims.

  For example, the circuit configuration of the charging device is not limited to the above example, and another member may be used as long as it has a similar function. Moreover, although the lithium battery was demonstrated to the example as a battery which performs constant current charge and constant voltage charge, in constant current charge, it can apply also to another battery with the risk of a deterioration of a battery and a fire.

  A pseudo temperature signal element other than a resistor may be used. The connection terminal is taken as an example of means for applying a temperature signal from the battery pack to the charging device, but other configurations capable of applying a signal may be used.

  The battery pack and the charging device according to the present invention can be used as a power source for a power tool and a charging device thereof.

The figure which shows the structure of the battery pack 1 The figure which connected the battery pack 1 to the charging device 2 The figure which connected the battery pack 130 to the charging device 2 Flowchart when battery pack 1 or battery pack 130 is connected to charging device 2 The figure which connected the battery pack 1 to the charging device 200 The figure which connected the battery pack 130 to the charging device 200 Flowchart when battery pack 1 or battery pack 130 is connected to charging device 200

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Battery pack, 1a battery, 1b Pseudo high temperature element, 1c Thermistor, 1d Battery type discrimination | determination element, 200 Charging apparatus, 90 1st battery temperature detection circuit, 100 2nd battery temperature detection circuit, 110 Battery type discrimination circuit

Claims (7)

A secondary battery charged by a charging device;
Charging permission / non-permission information providing means for allowing the charging device to determine whether charging is permitted or not; and
Battery pack with   The charging permission / non-permission means, when connected to a charging device capable of performing constant current charging and constant voltage charging, causes the charging device to determine permission of charging, and a charging device that performs only constant current charging. The battery pack according to claim 1, wherein, when connected, the charging device is made to determine whether or not charging is permitted.   4. The charging permission / non-permission unit includes a pseudo high temperature element indicating that a battery temperature of the secondary battery is equal to or higher than a predetermined value, and a temperature information element indicating the battery temperature. The battery pack according to any one of the above.   The battery pack according to any one of claims 1 to 3, wherein the secondary battery is a lithium ion battery.   The battery pack according to any one of claims 1 to 4, wherein the battery pack is for an electric tool. A charging circuit for supplying a charging current to the secondary battery constituting the battery pack;
A first temperature detecting means and a second battery temperature detecting means connected to the battery pack for detecting a battery temperature of the secondary battery;
With
When the second battery temperature detecting means is connected to the battery pack, it is determined whether or not the battery temperature is equal to or higher than a predetermined value, and charging is performed when it is determined that the battery temperature is lower than the predetermined value. When it is determined that the battery temperature is equal to or higher than a predetermined value, charging is not started,
Whether the second battery temperature detection means is not connected to the battery pack and only the first battery temperature detection means is connected to the battery pack, whether or not the battery temperature is equal to or higher than a predetermined value. The charging device is characterized in that charging is started when it is determined that the battery temperature is lower than a predetermined value, and charging is not started when it is determined that the battery temperature is higher than or equal to a predetermined value. Constant current control means for controlling the charging current of the charging circuit to a predetermined value;
Constant voltage control means for controlling the charging voltage of the charging circuit to a predetermined value;
Further comprising
When the second battery temperature detecting means is connected to the battery pack, it is determined whether or not the battery temperature is equal to or higher than a predetermined value, and when it is determined that the battery temperature is lower than the predetermined value, Depending on the state of charge of the secondary battery, the constant current control means and the constant voltage control means perform constant current charging and constant voltage charging,
When the second battery temperature detection means is not connected to the battery pack and only the first battery temperature detection means is connected to the battery pack, the first battery temperature detection means has the battery temperature equal to or higher than a predetermined value. The charging device according to claim 6, wherein constant current charging is performed by the constant current control means when it is determined whether or not the battery temperature is less than a predetermined value.

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