Charging system

Abstract

It can thaw the freezing of the charging lid or warm the battery without consuming the power of the vehicle's battery. [Solution] The charging system includes a fluid forward path built into the charging cable that supplies fluid from a heat-insulating container to a charging connector, a fluid return path built into the charging cable that returns fluid from the charging connector to the heat-insulating container, a connecting passage that connects the fluid forward path and the fluid return path within the charging connector, a switching valve that switches between a first circulation path that circulates fluid between the heat-insulating container and the charging connector via the fluid forward path, the fluid return path and the connecting passage, and a second circulation path that circulates fluid between the heat-insulating container and the storage battery via the fluid forward path, the vehicle-side fluid flow path and the fluid return path, and a control device that forms the first circulation path when it is necessary to raise the temperature of the charging lid, and forms the second circulation path when the charging lid is opened and the charging connector is connected to the charging inlet.

Description

Technical Field

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

Background Art

[0002] Conventionally, electric vehicles and hybrid vehicles that can charge an on-vehicle battery with an external power source are known. For example, in Patent Document 1, there are provided a connector connection portion having a charging inlet to which a charging connector extending from an external power source is connected during external charging, an openable and closable charging lid that covers the charging inlet, an electric heater provided in the connector connection portion, and a vehicle control device that energizes the electric heater when it is determined that the charging lid is frozen and the state of charge (SOC) of the battery is below a threshold value (see, for example, Patent Document 1). In this vehicle control device, in a low-temperature environment, the charging lid of the connector connection portion can be warmed by the electric heater, thereby eliminating the freezing of the charging lid. As a result, when starting external charging, the charging lid can be easily opened, so that external charging can be appropriately performed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above-described vehicle control device, since the heater for warming the connector connection portion is provided on the vehicle side, it operates by receiving power supply from the storage battery mounted on the vehicle. Therefore, it becomes difficult to use the heater in a situation where the SOC of the storage battery immediately before external charging is significantly decreased. Further, when charging a storage battery that cannot be charged at low temperature, such as a lithium-ion secondary battery, in a low-temperature environment, it is necessary to heat the storage battery to a temperature suitable for charging.

[0005] The primary objective of the charging system of this disclosure is to provide a charging system that can thaw the freezing of the charging lid or heat the battery without consuming the power of the battery installed in the vehicle. [Means for solving the problem]

[0006] The charging system of the present disclosure employs the following means to achieve the above-mentioned main objective. That is, the charging system of the present disclosure is for an electric vehicle comprising a battery, a charging inlet, an openable and closable charging lid covering the charging inlet from the outside, and a vehicle-side fluid passage that supplies a heat exchange fluid to the battery and heats the battery by heat exchange with the heat exchange fluid, wherein the charging system charges the battery by opening the charging lid and connecting the charging connector of a charging cable connected to an external power supply to the charging inlet, comprising: an external heating device for heating the heat exchange fluid, a heat-retaining container for storing the fluid heated by the external heating device, a fluid forward path built into the charging cable that supplies the heat exchange fluid from the heat-retaining container to the charging connector and is connected to one end of the vehicle-side fluid passage when the charging connector is connected to the charging inlet, and a front The gist of the invention is that it comprises: a fluid return path connected to the other end of the fluid passage on the vehicle side and which returns the heat exchange fluid from the charging connector to the heat-insulating container; a connecting passage that connects the fluid forward path and the fluid return path within the charging connector; a switching valve that switches between a first circulation path that circulates the heat exchange fluid between the heat-insulating container and the charging connector via the fluid forward path, the fluid return path and the connecting passage, and a second circulation path that circulates the heat exchange fluid between the heat-insulating container and the storage battery via the fluid forward path, the fluid passage on the vehicle side and the fluid return path; and a control device that controls the switching valve so that the heat exchange fluid circulates via the first circulation path when it is necessary to raise the temperature of the charging lid, and controls the switching valve so that the heat exchange fluid circulates via the second circulation path when the charging lid is opened and the charging connector is connected to the charging inlet.

[0007] In the charging system of this disclosure, a heat exchange fluid heated by an external heating device is stored in the insulated container. By circulating the heat exchange fluid between the insulated container and the charging connector while the charging connector is in contact with the charging lid, the charging lid can be warmed via the charging connector, thereby preventing the charging lid from freezing. Furthermore, when the charging lid is opened and the charging connector is connected to the charging inlet, circulating the heat exchange fluid between the insulated container and the on-board battery brings the battery temperature to a suitable temperature for charging. As a result, a charging system can be created that can prevent the charging lid from freezing and heat the battery without consuming the power of the on-board battery. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram of the charging system of this embodiment. [Figure 2] This is an explanatory diagram for the lid defrosting mode and battery heating mode. [Figure 3] This flowchart shows an example of external charging control. [Modes for carrying out the invention]

[0009] Next, we will describe the forms for implementing this disclosure.

[0010] Figure 1 is a schematic diagram of the charging system 1 of this embodiment. As shown in Figure 1, the charging system 1 of this embodiment is a system for charging a drive battery 110 mounted on an electric vehicle 100 (for example, an electric vehicle or a plug-in hybrid vehicle) using an external charger 20 provided by the charging equipment 10, and comprises an external charger 20, a charging cable 21, an external heating device 30, and a control device 40.

[0011] The electric vehicle 100 includes a drive battery 110, a charging inlet 120, a charging lid 121, a vehicle-side hot water supply line 131 and a vehicle-side hot water return line 132, and an electronic control unit (hereinafter referred to as "ECU") 140. The drive battery 110 is, for example, a lithium-ion secondary battery, and supplies power to the drive motor and other components of the electric vehicle 100. The charging inlet 120 is housed in a lid box having an opening on the outer surface of the vehicle body. The charging lid 121 is attached to the vehicle body, for example, via a hinge mechanism, and opens and closes the opening of the lid box. When the opening of the lid box is open, the charging inlet 120 is exposed to the outside, and the charging connector 22 of the charging cable 21 can be attached and detached. When the charging connector 22 is attached to the charging inlet 120, the power line 111 connected to the drive battery 110 is electrically connected to the external charger 20. The charging inlet 120 may be provided on the side of the electric vehicle 100 or on the bottom of the electric vehicle 100. The vehicle-side hot water supply path 131 and the vehicle-side hot water return path 132 are connected to the drive battery 110 and supply hot water to heat the drive battery 110 by heat exchange. The ECU 40 includes a CPU, ROM, RAM, input / output ports, communication ports, etc. The ECU 40 receives input such as the battery temperature from a temperature sensor 141 that detects the temperature of the drive battery 110 and the charge / discharge current from a current sensor (not shown) attached to the output terminal of the drive battery 110. The ECU 40 also calculates the state of charge (SOC) of the drive battery 110 based on the input charge / discharge current.

[0012] The external charger 20 is connected to the AC power supply E and the charging cable 21. When the charging connector 22 of the charging cable 21 is connected to the charging inlet 120, the external charger 20 converts the AC power from the AC power supply E into DC power, adjusts the voltage of the converted DC power, and outputs it to the drive battery 110.

[0013] The external heating device 30 is installed in the charging equipment 10 together with the external charger 20, and comprises a heat-insulating container 31 and an electric heater 32 built into the heat-insulating container 31. The external heating device 30 may also be built into the external charger 20. The heat-insulating container 31 is a container with heat insulation properties and stores hot water heated by the electric heater 32. The heat-insulating container 31 is connected to a hot water supply path 33 on the charging equipment side and a hot water return path 34 on the charging equipment side. A circulation pump 35 is installed in the hot water supply path 33 on the charging equipment side, and the hot water in the heat-insulating container 31 is pumped to the hot water supply path 33 on the charging equipment side by driving the circulation pump 35.

[0014] The hot water supply path 33 and the hot water return path 34 on the charging equipment side are built into the charging cable 21. As shown in Figure 2, the mounting surface of the charging connector 22 with the charging inlet 110 is provided with a hot water outlet 33a for the hot water supply path 33, a hot water inlet 34a for the hot water return path 34, an on-off valve 36 for opening and closing the hot water outlet 33a, and an on-off valve 37 for opening and closing the hot water inlet 34a. Furthermore, inside the charging connector 22, there is a connecting passage 38 that connects the hot water supply path 33 and the hot water return path 34, and an on-off valve 39 for opening and closing the connecting passage 38. The on-off valves 36, 37, and 39 are normally closed.

[0015] The external heating device 30 has two operating modes: a lid defrosting mode and a battery heating mode. The lid defrosting mode is a mode for defrosting the charging lid 121 so that it can be opened when the charging lid 121 is frozen and cannot be opened in a low-temperature environment, and is performed with the charging connector 22 in contact with the outer surface of the closed charging lid 121. The battery heating mode is a mode for heating the drive battery 110 in a low-temperature environment so that the low-temperature drive battery 110 rises to a temperature suitable for charging, and is performed with the charging lid 121 open and the charging connector 22 attached to the charging inlet 120.

[0016] In lid defrosting mode, as shown in Figure 2(a), valves 36 and 37 are closed and valve 39 is opened. This creates a circulation path (first circulation path) between the insulated container 31 and the charging connector 22, consisting of the charging equipment side hot water supply path 33, the connecting passage 38, and the charging equipment side hot water return path 34. Therefore, by driving the circulation pump 35, the charging connector 22 can be heated by the hot water stored in the insulated container 31, and by transferring heat to the charging lid 121 via the charging connector 22, the frozen charging lid 121 can be heated and defrosted.

[0017] In battery heating mode, as shown in Figure 2(b), the charging connector 22 is attached to the charging inlet 120, the hot water outlet 33a of the charging equipment side hot water supply path 33 is connected to the vehicle side hot water supply path 131, and the hot water inlet 34a of the charging equipment side hot water supply path 34 is connected to the vehicle side hot water return path 132. With these settings, the on-off valves 36 and 37 are opened and the on-off valve 39 is closed. This creates a circulation path (second circulation path) between the insulated container 31 and the drive battery 110, consisting of the charging equipment side hot water supply path 33, the vehicle side hot water supply path 131, the vehicle side hot water return path 132, and the charging equipment side hot water return path 34. Therefore, by driving the circulation pump 35, the hot water stored in the insulated container 31 can be supplied to the drive battery 110, and the drive battery 110 can be heated by heat exchange with the drive battery 110.

[0018] The control device 40 includes a CPU, ROM, RAM, input / output ports, and communication ports. The control device 40 receives inputs such as ambient temperature from the ambient temperature sensor 41 and water temperature from the temperature sensor 42 installed in the insulated container 31 via its input ports. The control device 40 also outputs control signals to the external charger 20, drive signals to the electric heater 32, and drive signals to the circulation pump 35 via its output ports. Furthermore, when the charging equipment 10 and the electric vehicle 100 are connected by the charging cable 21, the control device 40 is able to communicate with the ECU 40 of the electric vehicle 100 via a communication line built into the charging cable 21.

[0019] Next, the operation of the charging system 1 configured in this way will be described. In particular, the operation when charging the drive battery 110 by the external charger 20 in a low-temperature environment will be described. FIG. 3 is a flowchart showing an example of an external charging control process executed by the control device 40.

[0020] When the external charging control process is executed, the control device 40 first determines whether or not the outside air temperature input from the outside air temperature sensor 41 is equal to or lower than a threshold value (for example, 0°C) (step S100). If the control device 40 determines that the outside air temperature is not equal to or lower than the threshold value, it proceeds to step S116. On the other hand, if the control device 40 determines that the outside air temperature is equal to or lower than the threshold value, it drives the electric heater 32 to start heating the water in the heat storage container 31 (step S102). Then, when the water temperature input from the temperature sensor 42 reaches the set temperature (step S104), the control device 40 controls the electric heater 32 so that the warm water is kept at the set temperature (step S106).

[0021] Next, the control device 40 determines whether or not the charging connector 22 is in contact with the outer surface of the charging lid 121 (step S108). This process can be performed by determining whether or not the charging connector 22 is in contact with the charging lid 121 based on a signal from a touch sensor attached to the charging connector 22. If the control device 40 determines that the charging connector 22 is in contact with the outer surface of the charging lid 121, it closes the on-off valves 36 and 37 and opens the on-off valve 39 so as to form a warm water circulation path between the heat storage container 31 and the charging connector 22 (step S110), controls the circulation pump 35 so that the warm water in the heat storage container 31 is supplied to the charging connector 22 (step S112), and returns to step S108. On the other hand, if the control device 40 determines that the charging connector 22 is not in contact with the outer surface of the charging lid 121, it stops the supply of warm water to the charging connector 22 (step S114) and proceeds to step S116.

[0022] Next, the control device 40 determines whether the charging connector 22 is connected to the charging inlet 120 by means of a sensor (not shown) (step S116). If the control device 40 determines that the charging connector 22 is not connected to the charging inlet 120, it returns to step S108. On the other hand, if the control device 40 determines that the charging connector 22 is connected to the charging inlet 120, it controls the external charger 20 so that charging of the drive battery 110 is started (step S118). Subsequently, the control device 40 opens the on-off valves 36 and 37 and closes the on-off valve 39 so as to form a hot water circulation path between the heat insulation container 31 and the drive battery 110 (step S120). Next, the control device 40 obtains the temperature of the drive battery 110 (battery temperature) from the ECU40 on the electric vehicle 100 side through communication, and determines whether the obtained battery temperature is equal to or higher than a threshold value (for example, 5°C) (step S122). If the control device 40 determines that the battery temperature is lower than the threshold value, it controls the circulation pump 35 so that hot water is supplied to the drive battery 110 (step S124), and proceeds to step S128. On the other hand, if the control device 40 determines that the battery temperature is equal to or higher than the threshold value, it stops the supply of hot water (step S126), and proceeds to step S128.

[0023] Next, the control device 40 obtains the state of charge SOC of the drive battery 110 from the ECU40 on the electric vehicle 100 side, and determines whether the obtained state of charge SOC is equal to or higher than a target ratio (step S128). If the control device 40 determines that the state of charge SOC is not equal to or higher than the target ratio, it returns to step S122. If the control device 40 determines that the state of charge SOC is equal to or higher than the target ratio, it stops charging (step S130), and ends the external charging control process.

[0024] As described above, the embodiments for implementing the present disclosure have been described using examples. However, the present disclosure is not limited to such examples, and it is needless to say that the present disclosure can be implemented in various forms without departing from the gist of the present disclosure.

Industrial Applicability

[0025] This disclosure is applicable to the manufacturing industry of charging systems. [Explanation of Symbols]

[0026] 20 Charging system, 21 Charging cable, 22 Charging connector, 30 External heating device, 31 Insulated container, 33 Charging equipment side hot water supply path (hot water supply path), 34 Charging equipment side hot water return path (hot water return path), 36, 37, 39 On / off valves, 38 Connecting passage, 100 Electric vehicle, 110 Drive battery, 120 Charging inlet, 121 Charging lid, 131 Vehicle side hot water supply path (vehicle side fluid flow path), 132 Vehicle side hot water return path (vehicle side fluid flow path).

Claims

[Claim 1] An electric vehicle comprising a storage battery, a charging inlet, an openable and closable charging lid covering the charging inlet from the outside, and a vehicle-side fluid passage that supplies a heat exchange fluid to the storage battery and heats the storage battery by heat exchange with the heat exchange fluid, wherein the charging system charges the storage battery by opening the charging lid and connecting the charging connector of a charging cable connected to an external power supply to the charging inlet, An external heating device for heating the heat exchange fluid, A heat-retaining container for storing the fluid heated by the external heating device, A fluid forward path is built into the charging cable and supplies the heat exchange fluid from the heat-retaining container to the charging connector, and is connected to one end of the vehicle-side fluid flow path when the charging connector is connected to the charging inlet, The charging cable includes a fluid return path which is connected to the other end of the vehicle-side fluid passage when the charging connector is connected to the charging inlet, and which returns the heat exchange fluid from the charging connector to the heat-retaining container, Within the charging connector, a communication passage is provided to connect the fluid forward path and the fluid return path. A switching valve that switches between a first circulation path that circulates the heat exchange fluid between the heat-insulating container and the charging connector via the fluid supply path, the fluid return path, and the communication passage, and a second circulation path that circulates the heat exchange fluid between the heat-insulating container and the storage battery via the fluid supply path, the vehicle-side fluid flow path, and the fluid return path, A control device that controls the switching valve so that the heat exchange fluid circulates through the first circulation path when it is necessary to raise the temperature of the charging lid, and controls the switching valve so that the heat exchange fluid circulates through the second circulation path when the charging lid is opened and the charging connector is connected to the charging inlet, A charging system equipped with the following features.

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