Charging system

Abstract

To provide a charging system capable of suppressing the occurrence of insufficient charging.SOLUTION: A charging system 10 for charging a first storage battery 31 that is the target of charging includes a second storage battery 100 that stores power for charging the first storage battery 31, a communication unit 106 that receives a required amount, which is the charging amount required for the first storage battery 31, a temperature sensor 104 that measures the temperature of the second storage battery, a temperature control unit 105 that adjusts the temperature of the second storage battery 100, and a control unit 107 that increases the temperature of the second storage battery 100 using the temperature control unit 105 when the dischargeable amount of the second storage battery 100 which is determined using the temperature detected by the temperature sensor 104 and the remaining battery capacity of the second storage battery 100 is less than the required amount.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a charging system. [Background technology]

[0002] With the widespread use of electric vehicles equipped with storage batteries, there is a demand for various technologies related to charging storage batteries. In this regard, for example, Patent Document 1 discloses a technology for rapid charging a storage battery to be charged using a rapid charging device equipped with a storage battery with high output density and a storage battery with high energy density. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-034554 A Summary of the Invention [Problem to be solved by the invention]

[0004] The technology disclosed in Patent Document 1 does not manage the temperature of the storage battery that supplies power to the storage battery to be charged. Therefore, there is a possibility that the storage battery may be discharged when the temperature of the storage battery to be charged is low, and in that case, there is a risk that the battery may not be discharged sufficiently and the required amount of charge may not be secured.

[0005] The present disclosure has been made in light of the above-mentioned circumstances, and has an object to provide a charging system capable of suppressing the occurrence of insufficient charging. [Means for solving the problem]

[0006] One aspect of the present disclosure to achieve the above-mentioned object is a charging system for charging a first storage battery to be charged, the charging system having: a second storage battery storing power for charging the first storage battery; a communication unit receiving a required amount, which is the amount of charge required for the first storage battery; a temperature sensor measuring the temperature of the second storage battery; a temperature control unit adjusting the temperature of the second storage battery; and a control unit causing the temperature control unit to raise the temperature of the second storage battery when the dischargeable amount of the second storage battery determined using the temperature detected by the temperature sensor and the remaining battery charge of the second storage battery is less than the required amount.

[0007] In one aspect described above, the control unit may charge the first storage battery by supplying power from an AC power source if the temperature of the second storage battery does not reach a temperature at which the dischargeable amount of the second storage battery is equal to or greater than the required amount by the time charging of the first storage battery starts.

[0008] In one of the above aspects, when the temperature of the second storage battery reaches a temperature at which the dischargeable amount of the second storage battery is equal to or greater than the required amount, the control unit may switch from charging the first storage battery by supplying power from the AC power source to charging the first storage battery by supplying power from the second storage battery.

[0009] In the above aspect, the first storage battery may be mounted on a vehicle, the communication unit may further receive location information of the vehicle, and the control unit may estimate the charging start timing based on the location information. Effect of the Invention

[0010] According to the present disclosure, it is possible to provide a charging system capable of suppressing the occurrence of insufficient charging. [Brief description of the drawings]

[0011] [Figure 1] 1 is a block diagram showing an example of a configuration of a charging system according to an embodiment; [Diagram 2] FIG. 11 is a block diagram showing an example of another configuration of the charging system according to the embodiment. [Diagram 3] 1 is a table showing an example of a relationship between the temperature of a storage battery and the dischargeable amount of the storage battery. [Figure 4] 4 is a flowchart showing an example of an operation of the charging system according to the embodiment. [Diagram 5] FIG. 2 is a block diagram showing an example of a hardware configuration of a control unit as a computer. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment will be described with reference to the drawings. FIG. 1 is a block diagram showing an example of a configuration of a charging system 10 according to the embodiment. The charging system 10 is a system that charges a storage battery 31 to be charged that is mounted on a vehicle 30 or the like. In this embodiment, the charging system 10 is capable of rapid charging of the storage battery 31, and therefore the charging system 10 may be referred to as a rapid charging system. The vehicle 30 is, for example, an electric vehicle such as a plug-in hybrid electric vehicle (PHEV) or a battery electric vehicle (BEV) including a storage battery 31 that can be charged from outside the vehicle 30. Note that, in this embodiment, as an example, the storage battery 31 to be charged is described as being mounted on the vehicle 30, but the storage battery 31 does not necessarily have to be mounted on the vehicle. The storage battery 31 is a rechargeable secondary battery, for example, a lithium ion battery or the like, but the type of the secondary battery is not particularly limited.

[0013] The charging system 10 is connected to an AC power source 20 and an AC power source 21. The AC power source 20 and the AC power source 21 are commercial power sources that supply AC current of, for example, 100 volts or 200 volts. Although two AC power sources 20 and 21 are illustrated in FIG. 1, one AC power source that functions in place of these AC power sources may be used. As illustrated in FIG. 1, the charging system 10 includes a storage battery 100, an AC / DC converter 101, a DC / DC converter 102, a switch 103a, a switch 103b, a temperature sensor 104, a temperature adjustment unit 105, a communication unit 106, and a control unit 107.

[0014] The storage battery 100 is a storage battery that stores power for charging the storage battery 31 to be charged. That is, the storage battery 100 is a storage battery that supplies power to the storage battery 31 to be charged. The storage battery 100 may be called a power supply storage battery in order to distinguish it from the storage battery 31 to be charged. The storage battery 100 is a rechargeable secondary battery, for example, a secondary battery such as a lithium ion battery, but the type of the secondary battery is not particularly limited. In this embodiment, the storage battery 100 is charged by power supply from the AC power source 20. That is, the storage battery 100 stores electricity supplied from the AC power source 20, and outputs the stored electricity to the storage battery 31 to be charged under the control of a control unit 107 to be described later. Specifically, the storage battery 100 is connected to the AC power source 20 via an AC / DC converter 101. In addition, when the storage battery 31 to be charged is connected to the charging system 10, the storage battery 100 is connected to the storage battery 31 via a DC / DC converter 102.

[0015] The AC / DC converter 101 converts the AC power supplied from the AC power source 20 into DC power, and also transforms the voltage as necessary before outputting the DC power to the storage battery 100 to charge the storage battery 100. The DC / DC converter 102 converts the DC power from the storage battery 100 into a voltage and current required for charging the storage battery 31, and outputs the same to the storage battery 31. In this way, the storage battery 31 is charged using the storage battery 100.

[0016] The storage battery 100 is provided with a temperature sensor 104 that measures the temperature of the storage battery 100. The temperature measured by the temperature sensor 104 is notified to a control unit 107, which will be described later. The charging system 10 also has a temperature adjustment unit 105 that adjusts the temperature of the storage battery 100. In this embodiment, the temperature adjustment unit 105 includes a heater, such as a heater, that heats the storage battery 100 to increase the temperature of the storage battery 100. The temperature adjustment unit 105 may further include a cooler, such as a chiller or a fan, that cools the storage battery 100 to decrease the temperature of the storage battery 100. In the configuration shown in FIG. 1, the temperature adjustment unit 105 is driven by power supplied from an AC power source 20.

[0017] In this embodiment, the charging system 10 is capable of DC charging (i.e., charging with direct current power) of the storage battery 31 using the storage battery 100, as well as AC charging (i.e., charging with alternating current power) of the storage battery 31 using the alternating current power source 21. That is, the charging system 10 is capable of a first charging (DC charging) by supplying power from the storage battery 100 to the storage battery 31, and a second charging (AC charging) by supplying power from the alternating current power source 21 to the storage battery 31. This second charging can also be said to be charging without using the storage battery 100.

[0018] To switch between AC charging and DC charging, the charging system 10 has a switch 103a and a switch 103b. The switch 103a is a switch for controlling the execution of DC charging. In the configuration example shown in FIG. 1, the switch 103a is connected to the output terminal of the DC / DC converter 102, and is interposed between the storage battery 31 and the DC / DC converter 102 when the storage battery 31 to be charged is connected to the charging system 10. That is, the input terminal of the switch 103a is connected to the output terminal of the DC / DC converter 102, and the output terminal of the switch 103a is connected to the output terminal of the charging system 10. Therefore, when the switch 103a is in an off state, electricity for DC charging is not output from the output terminal of the charging system 10. In this way, the storage battery 31 is connected to the storage battery 100 and the DC / DC converter 102 via the switch 103a. Therefore, when the switch 103a is in an on state, power is supplied from the storage battery 100 to the storage battery 31, and DC charging of the storage battery 31 is performed. On the other hand, when the switch 103a is in the OFF state, the supply of power from the storage battery 100 to the storage battery 31 is cut off, and DC charging of the storage battery 31 is not performed.

[0019] The switch 103b is a switch for controlling the execution of AC charging. In the configuration example shown in FIG. 1, the switch 103b is connected to the AC power source 21, and is interposed between the storage battery 31 and the AC power source 21 when the storage battery 31 to be charged is connected to the charging system 10. That is, the input terminal of the switch 103b is connected to the AC power source 21, and the output terminal of the switch 103b is connected to the output terminal of the charging system 10. In the example shown in FIG. 1, the output terminal of the switch 103b is connected between the output terminal of the switch 103a and the output terminal of the charging system 10, but the output terminal of the charging system 10 to which the output terminal of the switch 103b is connected may be a terminal different from the output terminal of the charging system 10 to which the output terminal of the switch 103a is connected. Since the switch 103b is between the output terminal of the charging system 10 and the AC power source 21, when the switch 103b is in an off state, electricity for AC charging is not output from the output terminal of the charging system 10. In this manner, the storage battery 31 is connected to the AC power source 21 via the switch 103b. Therefore, when the switch 103b is in an on state, power is supplied from the AC power source 21 to the storage battery 31, and AC charging of the storage battery 31 is performed. In contrast, when the switch 103b is in an off state, the supply of power from the AC power source 21 to the storage battery 31 is cut off, and AC charging of the storage battery 31 is not performed. Note that, when AC charging is performed, the AC power output from the charging system 10 is converted into DC power within the vehicle 30 by an AC / DC converter (not shown) mounted on the vehicle 30 or the like, and is input to the storage battery 31.

[0020] The connection configuration shown in FIG. 1 is an example, and the charging system 10 may be a system having a connection configuration different from that shown in FIG. 1. For example, the charging system 10 may have a connection configuration as shown in FIG. 2. The configuration shown in FIG. 2 is different from the configuration shown in FIG. 1 in that the switch 103b is present between the AC power source 20 and the AC / DC converter 101. Accordingly, the AC power source 21 is omitted in the configuration shown in FIG. 2. In the configuration example shown in FIG. 2, specifically, a first output terminal of the switch 103b is connected to an input terminal of the AC / DC converter 101, and the input terminal of the switch 103b is connected to the AC power source 20. In addition, the switch 103b has a second output terminal connected to an output terminal of the charging system 10 in addition to a first output terminal connected to an input terminal of the AC / DC converter 101. In the example shown in FIG. 2, the second output terminal of the switch 103b is connected between the output terminal of the switch 103a and the output terminal of the charging system 10, but the output terminal of the charging system 10 to which the second output terminal of the switch 103b is connected may be a terminal different from the output terminal of the charging system 10 to which the output terminal of the switch 103a is connected. In the configuration shown in FIG. 2, the switch 103b controls the execution of AC charging by controlling the output of power from the second output terminal. Note that, although specific connection examples of the switch 103a and the switch 103b have been shown with reference to FIGS. 1 and 2, the switch 103a can be provided at any position where the execution of DC charging can be controlled, and the switch 103b can be provided at any position where the execution of AC charging can be controlled.

[0021] The charging system 10 also includes a communication unit 106 for communicating with an external device. The communication unit 106 includes a transmission / reception circuit and performs wireless communication with other devices. For example, the communication unit 106 communicates with a terminal device such as a smartphone used by the vehicle 30 or a user of the vehicle 30 (for example, a driver of the vehicle 30), and receives information used for controlling the charging system 10 as necessary. In the present embodiment, in particular, the communication unit 106 receives a charge amount required for the storage battery 31 (hereinafter also referred to as a required amount). The required amount received by the communication unit 106 may be used as an end condition for charging the storage battery 31. When the charge amount for the storage battery 31 reaches the required amount received as the end condition, the control unit 107 ends the charging of the storage battery 31. In the present embodiment, the communication unit 106 receives position information of the vehicle 30 so that the charging system 10 can grasp the time required for the vehicle 30 to arrive at a charging spot equipped with the charging system 10. Note that the communication unit 106 may receive information other than the above-mentioned information. For example, the communication unit 106 may receive state information of the storage battery 31, such as the remaining battery capacity (SOC: State Of Charge) of the storage battery 31.

[0022] The charging system 10 also includes a control unit 107 that controls the operation of the charging system 10. The control unit 107 is connected to the storage battery 100, the AC / DC converter 101, the DC / DC converter 102, the switch 103a, the switch 103b, the temperature sensor 104, the temperature adjustment unit 105, and the communication unit 106. The control unit 107 acquires the charge amount from the storage battery 100 to the storage battery 31 (i.e., the charge amount by DC charging) when DC charging is performed, and acquires the charge amount from the AC power source 21 or 20 to the storage battery 31 (i.e., the charge amount by AC charging) when AC charging is performed. The control unit 107 may also acquire the remaining battery capacity of the storage battery 100. The charge amount and the remaining battery capacity can be measured or estimated by a known technique, and the specific measurement or estimation method is not particularly limited. In the present embodiment, the control unit 107 acquires the temperature of the storage battery 100 from the temperature sensor 104 in particular.

[0023] Also, the control unit 107 can switch between a first charging (i.e., DC charging) by supplying power from the storage battery 100 to the storage battery 31 and a second charging (i.e., AC charging) by supplying power from the AC power source 21 or 20 to the storage battery 31. Specifically, as described above, the control unit 107 switches the switch 103a and the switch 103b on and off to switch between DC charging and AC charging. That is, when DC charging is performed, the control unit 107 switches the switch 103a to an on state and switches the switch 103b to an off state. Also, when AC charging is performed, the control unit 107 switches the switch 103a to an off state and switches the switch 103b to an on state. Note that, in the case of the configuration illustrated in FIG. 2, it is sufficient that the second output terminal of the switch 103b (the output terminal connected to the output terminal of the charging system 10) is in an off state during DC charging, and the first output terminal of the switch 103b (the output terminal on the AC / DC converter 101 side) may be in an on state or an off state. In the case of the configuration illustrated in FIG. 2, during AC charging, it is sufficient that the second output terminal of the switch 103b (the output terminal connected to the output terminal of the charging system 10) is in the on state, and the first output terminal of the switch 103b (the output terminal on the AC / DC converter 101 side) may be in either the on state or the off state.

[0024] Incidentally, the output of power from a storage battery depends on the temperature of the storage battery. Specifically, if the temperature of the storage battery is too low, the output of power from the storage battery decreases. Therefore, when the temperature of the storage battery 100 is low, the storage battery 100 cannot discharge sufficiently, and there is a risk that the required amount received by the communication unit 106 (i.e., the charge amount required for the storage battery 31) cannot be secured. In this embodiment, the control unit 107 specifies the dischargeable amount of the storage battery 100 using the temperature of the storage battery 100 detected by the temperature sensor 104 and the remaining battery charge of the storage battery 100. Then, when the specified dischargeable amount is less than the required amount received by the communication unit 106 (i.e., the charge amount required for the storage battery 31), the control unit 107 causes the temperature adjustment unit 105 to increase the temperature of the storage battery 100. That is, in this case, the control unit 107 controls the temperature adjustment unit 105 to heat the storage battery 100 and increase the temperature of the storage battery 100. Here, the dischargeable capacity is the capacity that can be taken out of the storage battery 100 by discharging the storage battery 100, and is expressed in units of Ah (ampere-hours), for example. In this embodiment, as shown in the table of FIG. 3, the dischargeable capacity can be determined from the temperature of the storage battery 100 and the remaining battery capacity of the storage battery 100. That is, the dischargeable capacity of the storage battery 100 is calculated by multiplying the remaining battery capacity of the storage battery 100 by a predetermined magnification (i.e., coefficient) according to the temperature of the storage battery 100. Here, the magnification is a positive number equal to or less than 1, and in the example shown in FIG. 3, when the temperature of the storage battery 100 is equal to or less than 10 degrees, the magnification is set to a smaller value as the temperature becomes lower. Note that FIG. 3 merely shows an example of the relationship between the temperature of the storage battery, the remaining battery capacity of the storage battery, and the dischargeable capacity of the storage battery, and the above-mentioned magnification is appropriately set according to the characteristics of the storage battery 100. 3, when the temperature of the storage battery 100 is low, the dischargeable amount of the storage battery 100 increases by raising the temperature of the storage battery 100, so that the amount of charge required for the storage battery 31 can be covered by discharging the storage battery 100. Therefore, the occurrence of insufficient charging can be suppressed.

[0025] In addition, in this embodiment, if the temperature of the storage battery 100 does not reach the target temperature by the charging start timing of the storage battery 31, the control unit 107 may charge the storage battery 31 by AC charging. That is, in this case, the control unit 107 may charge the storage battery 31 by power supply from the AC power source 21 or 20. Here, the target temperature refers to a temperature at which the dischargeable amount of the storage battery 100 is equal to or greater than the charge amount required for the storage battery 31. That is, the target temperature refers to a temperature at which the dischargeable amount of the storage battery 100 is equal to or greater than the required amount. The target temperature can be specified, for example, by searching for a temperature at which the dischargeable amount is equal to or greater than the required amount based on the correspondence relationship between the temperature of the storage battery 100 and the dischargeable amount as shown in FIG. 3. In this way, the control unit 107 may charge the storage battery 31 by AC charging if the temperature adjustment for raising the temperature of the storage battery 100 to a temperature at which the dischargeable amount of the storage battery 100 is equal to or greater than the required amount is not completed in time for the charging start timing of the storage battery 31. This allows the storage battery 31 to be charged even while the temperature of the storage battery 100 is rising.

[0026] Furthermore, in the case where AC charging of the storage battery 31 is performed as the temperature of the storage battery 100 rises, the control unit 107 switches from AC charging of the storage battery 31 to DC charging of the storage battery 31 when the temperature of the storage battery 100 reaches the above-mentioned target temperature. That is, the control unit 107 switches from charging the storage battery 31 with power supplied from the AC power source 21 or 20 to charging the storage battery 31 with power supplied from the storage battery 100. This allows the storage battery 31 to be charged with a large current.

[0027] In this embodiment, the control unit 107 estimates the charging start timing of the storage battery 31 based on the position information of the vehicle 30 received by the communication unit 106. For example, the control unit 107 calculates the time until the vehicle 30 arrives from the position information of the vehicle 30 and the position information of the charging spot equipped with the charging system 10. For example, the control unit 107 estimates the arrival time of the vehicle 30 at the charging spot by calculating the time until the vehicle 30 arrives at the charging spot, assuming that the vehicle 30 moves a distance from the current position of the vehicle 30 to the charging spot at a predetermined speed. Then, the control unit 107 sets the estimated arrival time as the charging start timing. With this configuration, even if the charging start timing is not notified, control using the charging start timing can be executed.

[0028] Furthermore, the control unit 107 terminates charging the storage battery 31 according to the termination condition of charging. That is, when the termination condition is satisfied, the control unit 107 terminates the DC charging or AC charging being performed on the storage battery 31. Specifically, the control unit 107 switches the switch 103a or 103b to the OFF state. The termination condition of charging may be a termination condition received by the communication unit 106, or may be a termination condition that is uniformly determined regardless of the user. As the uniformly determined termination condition, a predetermined chargeable time (e.g., 30 minutes) may be used. In this case, the control unit 107 terminates charging the storage battery 31 when the charging time of the storage battery 31 reaches the chargeable time determined as the termination condition. When there are multiple termination conditions, the control unit 107 terminates charging the storage battery 31 when any of the termination conditions is satisfied.

[0029] When starting DC charging or AC charging, the control unit 107 may confirm that the connection between the vehicle 30 and the charging system 10 has been normally established. The control unit 107 may also perform control other than the above-mentioned control. For example, the control unit 107 may control the AC / DC converter 101 to adjust the current and voltage input to the storage battery 100, or may control the DC / DC converter 102 to adjust the current and voltage output to the storage battery 31.

[0030] Next, a description will be given of an example of the flow of operations of the charging system 10. Fig. 4 is a flowchart showing an example of operations of the charging system 10. Below, the example of operations of the charging system 10 will be described with reference to Fig. 4.

[0031] In step S100, the control unit 107 acquires information necessary for control. In this embodiment, in particular, the control unit 107 acquires the charge amount (i.e., the required amount) required for the storage battery 31 and the position information of the vehicle 30 via the communication unit 106. The control unit 107 also acquires the remaining battery charge and temperature of the storage battery 100. The temperature of the storage battery 100 is also acquired as appropriate when executing the process described later. The control unit 107 may also acquire an end condition (e.g., a chargeable time) that is uniformly determined regardless of the user from the memory 151 described later or the like. In this step, the control unit 107 may further acquire information other than the above-mentioned information, such as state information of the storage battery 31.

[0032] Next, in step S101, the control unit 107 determines whether the temperature of the storage battery 100 is sufficiently high. That is, the control unit 107 determines whether the temperature of the storage battery 100 is higher than the temperature at which a decrease in the dischargeable amount occurs due to a low temperature. Specifically, the control unit 107 determines whether the temperature measured by the temperature sensor 104 is equal to or higher than a predetermined threshold. In the example shown in FIG. 3, the threshold is, for example, 20 degrees, but other values ​​may be used as the threshold. If the temperature of the storage battery 100 is equal to or higher than the threshold (NO in step S101), the temperature increase process of the storage battery 100 is not necessary, and the process proceeds to step S114. In step S114, the control unit 107 controls the switches 103a and 103b to start DC charging of the storage battery 31 to be charged. Then, the process proceeds to step S115. On the other hand, if the temperature of the storage battery 100 is lower than the threshold (YES in step S101), the process proceeds to step S102.

[0033] In step S102, the control unit 107 calculates the dischargeable amount of the storage battery 100. Then, the process proceeds to step S103. In step S103, the control unit 107 determines whether or not the dischargeable amount of the storage battery 100 is equal to or greater than the charge amount (i.e., the required amount) required for the storage battery 31. Even if the dischargeable amount of the storage battery 100 is equal to or greater than the required amount (NO in step S103), the process proceeds to step S114 because the temperature increase process of the storage battery 100 is not necessary. Therefore, in this case, in step S114, the control unit 107 starts DC charging of the storage battery 31 to be charged by controlling the switches 103a and 103b. Then, the process proceeds to step S115. On the other hand, if the dischargeable amount of the storage battery 100 is less than the required amount (YES in step S103), the process proceeds to step S104.

[0034] In step S104, the control unit 107 controls the temperature adjustment unit 105 to start heating the storage battery 100. Then, in step S105, the control unit 107 calculates the time from the current time to the time when the vehicle 30 arrives at the charging spot equipped with the charging system 10 (hereinafter referred to as the arrival time) and the time required to heat the storage battery 100 to the target temperature (hereinafter referred to as the heating time). As described above, the arrival time is calculated based on the current position information of the vehicle 30. In addition, the heating time is calculated based on, for example, the difference between the current temperature of the storage battery 100 and the target temperature and the amount of heat output by the temperature adjustment unit 105. Next, in step S106, it is determined whether the calculated arrival time is equal to or longer than the calculated heating time. That is, the control unit 107 determines whether the temperature adjustment for increasing the temperature of the storage battery 100 to the target temperature is in time for the charging start timing of the storage battery 31. If the arrival time is equal to or longer than the heating time, that is, if the temperature adjustment is completed before the charging start timing (YES in step S106), the process proceeds to step S107. In this case, the processes from step S107 to step S109 and step S115 are performed.

[0035] In step S107, the control unit 107 determines whether the temperature of the storage battery 100 has reached the target temperature. When the temperature of the storage battery 100 has reached the target temperature (YES in step S107), the process proceeds to step S108, and the control unit 107 ends heating of the storage battery 100 by the temperature adjustment unit 105. When the vehicle 30 arrives at the charging spot, in step S109, the control unit 107 controls the switches 103a and 103b to start DC charging of the storage battery 31 to be charged. After the process of step S109, the process proceeds to step S115.

[0036] On the other hand, if the heating time is longer than the arrival time, that is, if the temperature adjustment is not completed by the charging start timing (NO in step S106), the process proceeds to step S110. In this case, the processes from step S110 to step S113 and step S115 are performed.

[0037] When the vehicle 30 arrives at a charging spot while the temperature of the storage battery 100 is being adjusted, in step S110, the control unit 107 controls the switches 103a and 103b to start AC charging of the storage battery 31 to be charged. Then, in step S111, the control unit 107 determines whether the temperature of the storage battery 100 has reached the target temperature. When the temperature of the storage battery 100 has reached the target temperature (YES in step S111), in step S112, the control unit 107 ends heating of the storage battery 100 by the temperature adjustment unit 105, and the process proceeds to step S113. In step S113, the control unit 107 executes switching from AC charging to DC charging by controlling the switches 103a and 103b. That is, the control unit 107 ends AC charging of the storage battery 31 and starts DC charging of the storage battery 31. After the process of step S113, the process proceeds to step S115.

[0038] When DC charging or AC charging continues, in step S115, the charging end condition is satisfied. As a result, the control unit 107 ends the charging of the storage battery 31. The control unit 107 may end the charging when the amount of charge of the storage battery 31 reaches a required amount, or may end the charging when the charging time of the storage battery 31 reaches a predetermined chargeable time.

[0039] The control unit 107 may be configured as a dedicated hardware circuit for realizing the above-mentioned processing of the control unit 107, or may be configured as a computer as shown in Fig. 5. Fig. 5 is a block diagram showing an example of a hardware configuration of the control unit 107 as a computer. In the example shown in Fig. 5, the control unit 107 has an input / output interface 150, a memory 151, and a processor 152.

[0040] The input / output interface 150 is an interface through which the control unit 107 communicates with other components in the charging system 10.

[0041] The memory 151 is configured, for example, by a combination of a volatile memory and a non-volatile memory. The memory 151 is used to store programs executed by the processor 152, data used in processing, etc. The memory 151 may include multiple memories.

[0042] The processor 152 performs the processing of the control unit 107 by reading and executing a program from the memory 151. In this case, the processing of the control unit 107 is performed, for example, by the processor 152 reading and executing a program from the memory 151. The processor 152 may be, for example, a microprocessor, a microprocessor unit (MPU), a central processing unit (CPU), or a graphics processing unit (GPU). The processor 152 may include multiple processors.

[0043] The embodiment has been described above. In this embodiment, when the dischargeable amount of the storage battery 100, which is determined using the temperature of the storage battery 100 and the remaining battery capacity of the storage battery 100, is less than the required charging amount for the storage battery 31, the control unit 107 causes the temperature adjustment unit 105 to increase the temperature of the storage battery 100. Therefore, the dischargeable amount of the storage battery 100, which has decreased due to low temperature, can be increased. This makes it possible to suppress the occurrence of insufficient charging of the storage battery 31. In particular, since the increase in temperature of the storage battery 100 enables DC charging with a large current to the storage battery 31 with a low remaining battery capacity, this embodiment is particularly effective for charging the storage battery 31 with a low remaining battery capacity.

[0044] The present invention is not limited to the above embodiment, and may be modified as appropriate without departing from the spirit and scope of the present invention. For example, when the remaining battery power of the storage battery 100 becomes zero during DC charging, the control unit 107 may switch from DC charging to AC charging. [Explanation of symbols]

[0045] 10 Charging System 20 AC power supply 21 AC power supply 30 Vehicles 31 Storage battery 100 Battery 101 AC / DC converter 102 DC / DC converter 103a Switch 103b Switch 104 Temperature Sensor 105 Temperature control unit 106 Communications Department 107 Control Unit 150 Input / Output Interface 151 Memory 152 processors

Claims

1. A charging system for charging a first storage battery that is a charging target, a second storage battery storing power for charging the first storage battery; A communication unit that receives a required amount of charge for the first storage battery; a temperature sensor for measuring a temperature of the second storage battery; a temperature control unit for controlling a temperature of the second storage battery; a control unit that increases a temperature of the second storage battery by the temperature adjustment unit when a dischargeable amount of the second storage battery specified using the temperature detected by the temperature sensor and a remaining battery amount of the second storage battery is smaller than the required amount; A charging system having

2. The control unit charges the first storage battery by supplying power from an AC power source when the temperature of the second storage battery does not reach a temperature at which the dischargeable amount of the second storage battery is equal to or greater than the required amount by a charging start timing of the first storage battery. The charging system of claim 1 .

3. When the temperature of the second storage battery reaches a temperature at which the dischargeable amount of the second storage battery is equal to or greater than the required amount, the control unit switches from charging the first storage battery by power supply from the AC power source to charging the first storage battery by power supply from the second storage battery. The charging system according to claim 2 .

4. The first storage battery is mounted on a vehicle, The communication unit further receives position information of the vehicle, The control unit estimates the charging start timing based on the position information.

4. The charging system according to claim 2 or 3.

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