Power supply device

Abstract

To provide a power supply device with improved usability.SOLUTION: A power supply device 1 includes: a plurality of ports P1 to P4 to each of which a cell pack can be attached; a DC / AC invertor 13 for outputting a predetermined voltage; relays RY1B to RY4B for switching electrical connection and disconnection between each of the ports P1 to P4 and the DC / AC invertor 13; cell temperature detection circuits 31 to 34 for acquiring temperature of cell packs BT1 to BT4 mounted on each of the ports P1 to P4, respectively; and a microcomputer 40 for controlling the relays RY1B to RY4B so as to discharge from one of the cell packs BT1 to BT4 to the DC / AC-inverter 13. The microcomputer 40 is configured to determine, based on temperatures of at least the cell packs BT1 to BT4, an order of precedence in which the cell packs BT1 to BT4 are to be discharged.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a power supply device. [Background technology]

[0002] Patent Document 1 discloses a power supply device to which multiple battery packs can be attached simultaneously. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-136853 A Summary of the Invention [Problem to be solved by the invention]

[0004] Conventional power supply devices are not able to automatically select a battery pack with an appropriate temperature for discharging, and there is room for improvement in terms of usability.

[0005] An object of the present invention is to provide a power supply device with improved usability. [Means for solving the problem]

[0006] One aspect of the present invention is a power supply device. A plurality of battery pack mounting portions; an output unit that outputs a predetermined voltage; a switching unit that switches between electrical connection and disconnection between each of the plurality of battery pack mounting units and the output unit; a temperature acquisition unit that acquires a temperature of a battery pack mounted in each of the plurality of battery pack mounting units; a control unit that controls the switching unit to discharge one of the battery packs to the output unit when the battery packs are attached to the battery pack attachment units; A power supply device comprising: The control unit is characterized in that it is configured to determine a priority order for discharging from among the plurality of battery packs, based on at least the temperatures of the plurality of battery packs acquired by the temperature acquisition unit. Effect of the Invention

[0007] According to the present invention, it is possible to provide a power supply device with improved usability. [Brief description of the drawings]

[0008] [Figure 1] 1A is a plan view of a power supply device 1 according to an embodiment of the present invention, and FIG. [Diagram 2] FIG. 1 is a plan view showing an example of a usage mode of the power supply device 1, in which battery packs BT1 to BT4 are connected to ports P1 to P4, a DC power source (AC adapter) 5 is connected to the DC input port 6, and an equipment side power cord 8 is connected to the AC output port 7. [Diagram 3] FIG. 2 is a circuit block diagram of the power supply device 1. [Figure 4] FIG. 1A is a flowchart of battery priority order calculation in the power supply device 1. FIG. 1B is a flowchart of operation detection of the output switch 10 in the power supply device 1. FIG. 1C is a flowchart related to switching of a battery pack to be discharged in the power supply device 1. FIG. 1D is a flowchart of charging control in the power supply device 1. [Diagram 5] (A) is a flowchart of the port n battery voltage ranking (S7) in Fig. 4(A). (B) is a flowchart of the port n battery temperature ranking (S11) in Fig. 4(A). (C) is a flowchart of the priority order determination (S17) in Fig. 4(A). [Figure 6] (A) is a visual diagram showing the relationship between the voltage range and the battery voltage rank, and the relationship between the temperature range and the battery temperature rank. (B) is a table summarizing the relationship between the battery voltage rank, battery temperature rank, battery rank, and priority order for discharging. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] This embodiment relates to a power supply device 1. The power supply device 1 is a portable power source. As shown in Fig. 1, the power supply device 1 has ports P1 to P4 as multiple battery pack attachment parts. The ports P1 and P2 are provided on the front side of a housing 3, and the ports P3 and P4 are provided on the rear side of the housing 3. As shown in Fig. 2, battery packs BT1 to BT4 can be attached (connected) simultaneously to the ports P1 to P4.

[0010] The battery packs BT1 to BT4 are, for example, battery packs for power tools having the same structure, containing secondary battery cells such as lithium-ion batteries, and each having a rated voltage of 18 V. The battery packs BT1 to BT4 may be battery packs whose output voltage switches between 18 V and 36 V depending on the terminal structure of the device to which they are connected. In this case, the ports P1 to P4 may have a terminal structure that makes the output voltage of the battery packs BT1 to BT4 18 V.

[0011] LEDs L1 to L4 are provided as status indicators at the four corners of the top surface of the housing 3. The LEDs L1 to L4 inform the user of the status of the battery packs BT1 to BT4 attached to the ports P1 to P4 depending on their lighting status. The status of the battery packs BT1 to BT4 includes, for example, discharging, standby, charging, remaining battery power, charging progress, etc.

[0012] A DC input port 6 and an AC output port 7 are provided on the side of the housing 3. As shown in Fig. 2, the output voltage of a DC power supply 5 (AC adapter) that converts an AC voltage supplied from an external AC power supply into a DC voltage, for example, 12V DC, is input to the DC input port 6 as an external power supply connection section. The AC output port 7 outputs 100V AC. A device side power cord 8, i.e., the power cord of an external device to be powered by the power supply device 1, is connected to the AC output port 7.

[0013] An output switch 10 and an output indicator lamp 15 are provided on the top surface of the housing 3. The output switch 10 is an operation unit that allows the user to switch between output and stop of the power supply device 1. The output indicator lamp 15 is, for example, an LED, and indicates the output state of the power supply device 1, i.e., whether or not 100V AC is being output to the AC output port 7.

[0014] A movable handle 16 used for carrying the power supply device 1 is rotatably connected to the upper surface of the housing 3.

[0015] FIG. 3 is a circuit block diagram of the power supply device 1.

[0016] The positive terminal of the DC power supply 5 (the positive terminal of the DC input port 6) is connected to the input terminal of the control power supply 38 via a fuse F5 and a diode 15. The positive terminal of the DC power supply 5 is also connected to the positive input terminal (+in) of the DCDC converter 11 via a fuse F5. The negative terminal of the DC power supply 5 (the negative terminal of the DC input port 6) is connected to the ground and the negative input terminal (-in) of the DCDC converter 11.

[0017] The positive output terminal (+out) of the DCDC converter 11 is connected to the C+ terminal (C+ terminal of port P1) of the battery pack BT1 via a diode D1A and a relay RY1A, to the C+ terminal (C+ terminal of port P2) of the battery pack BT2 via a diode D2A and a relay RY2A, to the C+ terminal (C+ terminal of port P3) of the battery pack BT3 via a diode D3A and a relay RY3A, and to the C+ terminal (C+ terminal of port P4) of the battery pack BT4 via a diode D4A and a relay RY4A. The negative output terminal (-out) of the DCDC converter 11 is connected to each of the - terminals (each of the - terminals of ports P1 to P4) of the battery packs BT1 to BT4 and to ground via a shunt resistor 12 for detecting the charging current.

[0018] The + terminal of the battery pack BT1 (the + terminal of port P1) is connected to the positive input terminal (+in) of the DCAC inverter 13 via a fuse F1, a relay RY1B, and a diode D1B. The + terminal of the battery pack BT1 is also connected to the input terminal of the control power supply 38 via a fuse F1, a diode D11, a switching element Q1, and a diode D16. The - terminal of the battery pack BT1 (the - terminal of port P1) is connected to ground.

[0019] The + terminal of the battery pack BT2 (the + terminal of port P2) is connected to the positive input terminal (+in) of the DCAC inverter 13 via a fuse F2, a relay RY2B, and a diode D2B. The + terminal of the battery pack BT2 is also connected to the input terminal of the control power supply 38 via a fuse F2, a diode D12, a switching element Q1, and a diode D16. The - terminal of the battery pack BT2 (the - terminal of port P2) is connected to ground.

[0020] The + terminal of the battery pack BT3 (the + terminal of port P3) is connected to the positive input terminal (+in) of the DCAC inverter 13 via a fuse F3, a relay RY3B, and a diode D3B. The + terminal of the battery pack BT3 is also connected to the input terminal of the control power supply 38 via a fuse F3, a diode D13, a switching element Q1, and a diode D16. The - terminal of the battery pack BT3 (the - terminal of port P3) is connected to ground.

[0021] The + terminal of the battery pack BT4 (the + terminal of port P4) is connected to the positive input terminal (+in) of the DCAC inverter 13 via a fuse F4, a relay RY4B, and a diode D4B. The + terminal of the battery pack BT4 is also connected to the input terminal of the control power supply 38 via a fuse F4, a diode D14, a switching element Q1, and a diode D16. The - terminal of the battery pack BT4 (the - terminal of port P4) is connected to ground.

[0022] A negative input terminal (-in) of the DCAC inverter 13 is connected to ground via a shunt resistor 14 for detecting an output current.

[0023] Battery voltage detection circuits 21-24 serving as a voltage detection unit are connected to the + terminals of the battery packs BT1-BT4 (respective + terminals of ports P1-P4). Battery temperature detection circuits 31-34 serving as a temperature acquisition unit are connected to the LS terminals of the battery packs BT1-BT4 (respective LS terminals of ports P1-P4). A power supply voltage detection circuit 25 is connected to the + terminal of the DC power supply 5 (the + terminal of the DC input port 6).

[0024] The power supply voltage detection circuit 25 detects the input voltage from the DC power supply 5 and transmits it to the microcomputer 40. The DCDC converter 11, under the control of the microcomputer 40, converts the DC voltage supplied from the DC power supply 5 into a DC voltage suitable for charging the battery packs BT1 to BT4 and supplies it to one of the battery packs BT1 to BT4. The DCDC converter 11 is a charging circuit that outputs charging power based on the input power from the DC power supply 5. The shunt resistor 12 converts the output current (charging current) of the DCDC converter 11 into a voltage and transmits it to the microcomputer 40.

[0025] The battery voltage detection circuits 21-24 detect the voltages of the battery packs BT1-BT4, respectively, and transmit them to the microcomputer 40. The battery temperature detection circuits 31-34 detect the temperatures of the battery packs BT1-BT4, respectively, based on signals (temperature signals) from the LS terminals of the battery packs BT1-BT4, and transmit them to the microcomputer 40.

[0026] The DCAC inverter 13 as a conversion unit converts the DC voltage output from any of the battery packs BT1 to BT4 into an AC voltage, for example, 100V AC, under the control of the microcomputer 40, and outputs it to the AC output port 7. The DCAC inverter 13 and the AC output port 7 constitute an output unit that outputs a predetermined voltage. The shunt resistor 14 detects the input current to the DCAC inverter 13, i.e., the output current of the battery pack that is discharging among the battery packs BT1 to BT4, and transmits it to the microcomputer 40.

[0027] The control power supply 38 converts the voltage of the DC power supply 5 or the voltage of any of the battery packs BT1 to BT4 into a power supply voltage for the microcomputer 40 (for example, 5 V DC) and supplies it to the microcomputer 40. The microcomputer 40 (microcontroller) is a control unit that controls the overall operation of the power supply device 1.

[0028] When the DC power supply 5 is connected to the DC input port 6, the microcomputer 40 selectively turns on the relays RY1A to RY4A, determines which of the battery packs BT1 to BT4 is to be connected to the output side of the DCDC converter 11, that is, determines which of the battery packs BT1 to BT4 is to be charged, and performs charging control (control of the DCDC converter 11). How to determine the charging priority of the battery packs BT1 to BT4 will be described later.

[0029] When the microcomputer 40 detects the operation of the output switch 10, it selectively turns on the relays RY1B to RY4B, determines which of the battery packs BT1 to BT4 is to be connected to the input side of the DCAC inverter 13, i.e., determines which of the battery packs BT1 to BT4 is to be discharged, and controls the DCAC inverter 13 to start outputting voltage to the AC output port 7. The relays RY1B to RY4B are switching units that switch between electrical connection and disconnection between each of the ports P1 to P4 and the DCAC inverter 13. How to determine the priority order for discharging the battery packs BT1 to BT4 will be described later.

[0030] When the DC power supply 5 is connected to the DC input port 6, the control power supply 38 is on and the microcomputer 40 is in an activated state regardless of the operation of the output switch 10. On the other hand, when the DC power supply 5 is not connected to the DC input port 6, the control power supply 38 and the microcomputer 40 are activated by the operation of the output switch 10.

[0031] Specifically, when the output switch 10 is turned on, the output current of the battery pack with the highest voltage among the battery packs BT1 to BT4 flows through a path of resistors R1, R2, diode D18, output switch 10, and ground. At this time, a voltage is generated between the gate and source of the switching element Q1 due to a voltage drop at the resistor R1, and the switching element Q1 is turned on. Then, the output voltage of the battery pack with the highest voltage among the battery packs BT1 to BT4 is input to the control power supply 38 via the switching element Q1 and diode D16, the control power supply 38 is started, a power supply voltage is supplied to the microcomputer 40, and the microcomputer 40 is started. At this time, the microcomputer 40 detects the ON state of the output switch 10 immediately after starting up, and starts control related to discharge. When the microcomputer 40 is started up, it outputs a hold signal to the switching element Q2 to maintain the switching element Q2 in the ON state. As a result, even if the output switch 10 is turned off, the switching element Q1 is maintained in the ON state, the control power supply 38 is maintained in the ON state, and the microcomputer 40 continues to be started up.

[0032] Fig. 4(A) is a flowchart of battery priority order calculation in the power supply device 1. This flowchart calculates the priority order of which of the battery packs BT1 to BT4 should be discharged first. The microcomputer 40 executes the process shown in Fig. 4(A) at regular intervals regardless of whether or not there is output to the AC output port 7.

[0033] When a battery pack is attached to any port n (n is any integer from 1 to 4) (Yes in S1), and the battery pack of port n is not outputting (discharging) (No in S3), the microcomputer 40 reads the voltage of the battery pack of port n (S5), ranks the voltage of the battery pack of port n (S7), reads the temperature of the battery pack of port n (S9), ranks the temperature of the battery pack of port n (S11), and calculates the battery rank of the battery pack of port n (S13). When the microcomputer 40 has finished calculating the battery ranks for all ports to be subjected to priority calculation, i.e., ports to which battery packs are attached and which are not used for output to the AC output port 7 (Yes in S15), it determines the priority order based on the battery rank (S17).

[0034] FIG. 4(B) is a flow chart of the power supply device 1 when detecting the operation of the output switch 10. When the microcomputer 40 detects the operation of the output switch 10, it sets the port with the highest priority (hereinafter, the "highest priority port") as the port (hereinafter, the "output port") to be used for output to the AC output port 7 (S21). The microcomputer 40 clears various ranks of the highest priority port, that is, the rank for voltage (hereinafter, the "battery voltage rank"), the rank for temperature (hereinafter, the "battery temperature rank"), and the battery rank (S23). The microcomputer 40 turns on the relay RYnB corresponding to the highest priority port, port n here (S25). As a result, the battery pack connected to the highest priority port n is discharged to the DCAC inverter 13, and AC voltage is output to the AC output port 7.

[0035] FIG. 4(C) is a flow chart for switching the battery pack to be discharged in the power supply device 1. When battery packs are attached to a plurality of ports (Yes in S31), and the voltage of the battery pack being outputted is low (lower than the discharge stop voltage) or the temperature of the battery pack being outputted is high (higher than the discharge stop temperature) (Yes in S33), the microcomputer 40 determines the second priority port m (m is an arbitrary integer from 1 to 4), that is, the port m having the highest priority among the battery packs not being outputted (S35). The microcomputer 40 turns off the relay RYnB corresponding to the port n being outputted (S37), clears various ranks of the second priority port m (S39), and turns on the relay RYmB corresponding to the second priority port m (S41). As a result, the battery pack connected to the second priority port m is discharged to the DCAC inverter 13, and the output of the AC voltage to the AC output port 7 is continued.

[0036] FIG. 4(D) is a flowchart of charging control in the power supply device 1. When there is power input from the DC power supply 5 to the DC input port 6 (Yes in S51), if the battery pack of port k (k is any integer from 1 to 4) with the lowest voltage is chargeable (Yes in S53), the microcomputer 40 selects the battery pack attached to port k as the charging target (S55) and turns on the relay RYkA corresponding to port k (S57). As a result, the battery pack attached to port k is charged from the DC power supply 5 via the DCDC converter 11. When the battery pack attached to port k cannot be charged due to high temperature or the like (No in S53), if the battery pack of port j (j is any integer from 1 to 4) with the next lowest voltage is chargeable (Yes in S59), the microcomputer 40 selects the battery pack attached to port j as the charging target (S61) and turns on the relay RYjA corresponding to port j (S63). As a result, the battery pack attached to port j is charged from the DC power supply 5 via the DCDC converter 11. Although not shown in the figure, if the battery pack attached to port j cannot be charged due to high temperature or other reasons (No in S59), it is possible to determine whether the battery pack in the port with the next lowest voltage can be charged, and repeat the process until a battery pack to be charged is found or it is determined that the battery packs in all ports are not eligible for charging.

[0037] Fig. 5(A) is a flowchart of the port n battery voltage ranking (S7) in Fig. 4(A). An example of the first threshold value to the fourth threshold value, which are the voltage threshold values ​​in this flowchart, is shown in Fig. 6(A).

[0038] If the voltage of the battery pack attached to port n (hereinafter "port n battery voltage") is equal to or lower than the first threshold value (No in S71), the microcomputer 40 sets the battery voltage rank of port n to 5 (S73).

[0039] If the port n battery voltage exceeds the first threshold (Yes in S71) and is equal to or lower than the second threshold (No in S75), the microcomputer 40 sets the battery voltage rank of port n to 4 (S77).

[0040] If the port n battery voltage exceeds the second threshold (Yes in S75) and is equal to or lower than the third threshold (No in S79), the microcomputer 40 sets the battery voltage rank of port n to 3 (S81).

[0041] If the port n battery voltage exceeds the third threshold (Yes in S79) and is equal to or lower than the fourth threshold (No in S83), the microcomputer 40 sets the battery voltage rank of port n to 2 (S85).

[0042] If the battery voltage of port n exceeds the fourth threshold value (Yes in S83), the microcomputer 40 sets the battery voltage rank of port n to 1 (S87).

[0043] Fig. 5(B) is a flowchart of the port n battery temperature ranking (S11) in Fig. 4(A). An example of the first threshold value to the fifth threshold value, which are the temperature threshold values ​​in this flowchart, is shown in Fig. 6(A).

[0044] If the temperature of the battery pack attached to port n (hereinafter "port n battery temperature") is equal to or lower than the first threshold or equal to or higher than the fifth threshold (No in S91), the microcomputer 40 sets the battery temperature rank of port n to 5 (S93).

[0045] If the port n battery temperature is greater than the first threshold and less than the fifth threshold (Yes in S91), and if the port n battery temperature is equal to or less than the second threshold (No in S95), the microcontroller 40 sets the battery temperature rank of port n to 2 (S97).

[0046] If the port n battery temperature exceeds the second threshold (Yes in S95) and is equal to or lower than the third threshold (No in S99), the microcomputer 40 sets the battery temperature rank of port n to 1 (S101).

[0047] If the battery temperature of port n exceeds the third threshold (Yes in S99) but is equal to or lower than the fourth threshold (No in S103), the microcomputer 40 sets the battery temperature rank of port n to 3 (S105).

[0048] If the battery temperature of port n exceeds the fourth threshold (Yes in S103), the microcomputer 40 sets the battery temperature rank of port n to 4 (S109).

[0049] Fig. 5(C) is a flow chart of the priority order determination (S17) of Fig. 4(A). Microcomputer 40 compares the battery ranks of each port and determines the highest priority port (S111).

[0050] FIG. 6(A) is a diagram visually showing the relationship between the voltage range and the battery voltage rank, and the relationship between the temperature range and the battery temperature rank.

[0051] 6A, the first threshold voltage is 15 V, the second threshold voltage is 16.5 V, the third threshold voltage is 18 V, and the fourth threshold voltage is 19.5 V. The microcomputer 40 is configured to increase the battery voltage rank every time the voltage exceeds each threshold voltage.

[0052] In the example of Fig. 6(A), the first threshold value for temperature is 0°C, the second threshold value is 10°C, the third threshold value is 30°C, the fourth threshold value is 60°C, and the fifth threshold value is 80°C. The microcomputer 40 is configured to lower the battery temperature rank as the temperature moves away from the normal region (the region above the second threshold value and below the third threshold value). This is because lithium-ion batteries, which are often used in battery packs, have increased internal resistance and reduced discharge capacity at low temperatures, while degradation accelerates when used at high temperatures.

[0053] Fig. 6(B) is a table summarizing the relationship between battery voltage rank, battery temperature rank, battery rank, and priority order in discharging. In the example of this figure, the battery rank is calculated as the product of the numerical value of the battery voltage rank and the numerical value of the battery temperature rank. However, battery packs with at least one of the battery voltage rank and battery temperature rank of 5 are excluded from the calculation of battery rank (excluding them from discharging). When battery ranks are the same, the priority order is given to the battery pack with the higher battery temperature rank.

[0054] This embodiment provides the following advantageous effects.

[0055] (1) The microcomputer 40 is configured to determine the priority order of which of the battery packs BT1 to BT4 to discharge, taking into account the temperatures of the battery packs BT1 to BT4. This allows automatic selection of a battery pack having a temperature suitable for discharging as the battery pack to be discharged, which is convenient. The power supply device 1 is configured to generate an AC voltage output from the AC output port 7 from the output voltage of a single battery pack, and since the temperature of a battery pack tends to rise during discharging, it is important to include temperature in the factors for determining the discharge priority order.

[0056] (2) The microcomputer 40 is configured to determine the priority order of which of the battery packs BT1 to BT4 should be discharged based on the temperature and voltage of the battery packs BT1 to BT4. This makes it possible to automatically select an appropriate battery pack as the battery pack to be discharged, taking into account both the temperature and the voltage, which is convenient.

[0057] (3) The microcomputer 40 is configured to lower the battery temperature rank as the temperature moves away from the normal range, for example, the range of 10° C. to 30° C. This makes it possible to suppress discharge from a battery pack whose discharge capacity has decreased at low temperatures or from a battery pack that is prone to deterioration at high temperatures, which is convenient to use.

[0058] (4) The microcontroller 40 automatically switches to output from the battery pack in the next priority port before the battery pack currently outputting becomes unable to output, thereby preventing interruption of the output of the power supply device 1 and extending the runtime.

[0059] (5) When there are multiple rechargeable battery packs, the microcomputer 40 is configured to control the relays RY1A to RY4A so that the battery packs are charged in order starting with the battery pack with the lowest voltage. This makes it possible to quickly recover the remaining power of a battery pack that is rapidly depleted, which is convenient to use.

[0060] (6) When the DC power supply 5 is not connected to the DC input port 6, the voltage of one of the battery packs BT1 to BT4 is supplied to the control power supply 38 when the output switch 10 is operated. As a result, the control power supply 38 and the microcomputer 40 are configured to be started by the operation of the output switch 10, so that the power consumption of the battery packs BT1 to BT4 is suppressed.

[0061] Although the present invention has been described above by taking the embodiment as an example, the present invention is not limited to the embodiment. Various modifications can be made to each of the details specifically described in the embodiment within the scope of the claims.

[0062] The voltages, temperatures, number of ports, number of battery voltage ranks, and number of battery temperature ranks given as specific numerical values ​​in the embodiments do not limit the scope of the invention in any way and can be changed as desired according to the required specifications. Relays RY1A to RY4A and relays RY1B to RY4B may be replaced with semiconductor switching elements. [Explanation of symbols]

[0063] 1...power supply (portable power supply), 3...housing, 5...DC power supply (AC adapter), 6...DC input port, 7...AC output port, 8...device power cord, 10...output switch, 11...DCDC converter, 12...shunt resistor, 13...DCAC inverter, 14...shunt resistor, 15...output indicator lamp, 16...movable handle, 21-24...battery voltage detection circuit, 25...power supply voltage detection circuit, 31-34...battery temperature detection circuit, 38...control power supply, 40...microcontroller (control unit), BT1-BT4...battery pack, L1-L4...LED, P1-P4...port (battery pack attachment part).

Claims

1. A plurality of battery pack mounting portions; an output unit that outputs a predetermined voltage; a switching unit that switches between electrical connection and disconnection between each of the plurality of battery pack mounting units and the output unit; a temperature acquisition unit that acquires a temperature of a battery pack mounted in each of the plurality of battery pack mounting units; a control unit that controls the switching unit to discharge one of the battery packs to the output unit when a plurality of battery packs are attached to the battery pack attachment units; A power supply device comprising: the control unit is configured to determine a priority order for discharging from among the plurality of battery packs, based on at least the temperatures of the plurality of battery packs acquired by the temperature acquisition unit. A power supply device comprising:

2. 2. The power supply device according to claim 1, a voltage detection unit for detecting a voltage of a battery pack mounted in each of the plurality of battery pack mounting units; the control unit is configured to determine the priority order based on temperatures of the plurality of battery packs acquired by the temperature acquisition unit and voltages of the plurality of battery packs detected by the voltage detection unit. A power supply device comprising:

3. 3. The power supply device according to claim 1, the control unit is configured to, when the voltages of the plurality of battery packs are equal, assign a lower priority to a battery pack whose temperature acquired by the temperature acquisition unit is farther from a normal region. A power supply device comprising:

4. 3. The power supply device according to claim 1, the control unit is configured to, when the voltages of the plurality of battery packs are equivalent, assign a lower priority to a battery pack whose temperature acquired by the temperature acquisition unit is in a range lower than the normal range than the priority of a battery pack whose temperature acquired by the temperature acquisition unit is in the normal range. A power supply device comprising:

5. 3. The power supply device according to claim 1, the control unit is configured to, when the voltages of the plurality of battery packs are equivalent, assign a lower priority to a battery pack whose temperature acquired by the temperature acquisition unit is in a range higher than the normal range than the priority of a battery pack whose temperature acquired by the temperature acquisition unit is in the normal range. A power supply device comprising:

6. The power supply device according to claim 1 or 2, The output unit has a conversion unit that converts a DC voltage output from the one battery pack into an AC voltage. A power supply device comprising:

7. The power supply device according to claim 1 or 2, An external power supply connection; a charging circuit that outputs charging power based on input power from the external power supply connection unit, the control unit is configured to charge the battery pack by the charging circuit in ascending order of voltage when the battery packs are mounted in the battery pack mounting portions. A power supply device comprising:

8. 3. The power supply device according to claim 1, A user operable switch; a control power supply that generates a power supply voltage for the control unit; When the switch is operated, a voltage of a battery pack connected to at least one of the plurality of battery pack mounting sections is supplied to the control power supply. A power supply device comprising:

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