GB2565603A

GB2565603A - Apparatus and methods

Info

Publication number: GB2565603A
Application number: GB1717943.3A
Authority: GB
Inventors: Barrass Peter
Original assignee: Sevcon Ltd
Current assignee: Sevcon Ltd
Priority date: 2017-08-08
Filing date: 2017-10-31
Publication date: 2019-02-20
Also published as: GB201717943D0; GB201712725D0

Abstract

A charging control unit 103 for providing charging currents to a plurality of devices 105 (for example, electric vehicles), to charge rechargeable electric batteries 106 in said devices, the control unit comprising, an AC-DC converter configured to convert an AC power supply 101 to a DC charging current, a plurality of connecting ports 104a-d wherein each port is configured to provide the charging current to a corresponding one of the devices. A controller, arranged between the converter and the plurality of connecting ports is configured to determine for each device, data comprising at least one of a charging state of that device and an available charge time of that device select one of the plurality of connecting ports based on the device data and provide the charging current to the selected connecting port. Selecting one of the charging ports may involve determining a charging schedule based on the data.

Description

Apparatus and Methods

Field

The present disclosure relates to apparatus and methods for charging rechargeable batteries, and more particularly to controlling a charging current to a plurality of rechargeable devices .

Background

Rechargeable batteries are commonly used in many technologies, for example in electric or hybrid vehicles. Charging stations for electric vehicles are currently being installed by public authorities, commercial enterprises and some major employers in order to stimulate the market for vehicles that use alternative fuels to gasoline and diesel fuels. Charging stations can be found where there is on-street parking, at taxi stands, in parking lots (at places of employment, hotels, airports, shopping centres, convenience shops, fast food restaurants, coffee-houses etc.), as well as in driveways and garages at home. Existing filling stations may also incorporate charging stations.

DC fast chargers are a type of charging station designed to quickly charge electric vehicles. DC fast charging stations may offer a restricted charge, stopping at a certain charge level, or may change the charging rate to a lower level after a certain charge level is reached.

Summary

Aspects of the invention are as set out in the independent claims and optional features are set out in the dependent claims .

In an aspect there is provided a charging control unit for providing charging currents to a plurality of devices, to charge rechargeable electric batteries in said devices, the control unit comprising an AC-DC converter configured to convert an AC power supply to a DC charging current; a plurality of connecting ports wherein each port is configured to provide the charging current to a corresponding one of the plurality of devices; a controller, arranged between the converter and the plurality of connecting ports, wherein the controller is configured to determine for each device, device data comprising at least one of a charging state of that device and an available charge time of that device; select one of the plurality of connecting ports based on the device data; and provide the charging current to the selected connecting port.

In an aspect there is provided a method of controlling charging currents to a plurality of devices for charging rechargeable electric batteries in said devices, comprising determining device data comprising at least one of: a charging state of that device, and an available charge time of that device; selecting one of the plurality of connecting ports based on the device data; and providing the charging current to the selected connecting port.

Each of the foregoing aspects may be further refined as s described herein.

Each rechargeable electric battery may have an energy storage capacity, and the charging state comprises an indication of energy stored in the battery as a proportion of the energy storage capacity. For example the associated charging state may comprise a percentage charge level of the battery.

The controller may be configured so that, in the event of a first device connecting to a first connecting port, the controller is configured to determine device data of the first device. For example the connecting ports may be configured to provide an indication to the controller in response to a device coupling to a port of the control unit to the controller. For example the controller may obtain an associated charging state from a connected device and may obtain an available charge time from the device or a user interface .

Selecting one of the plurality of connecting ports may comprise, in the event of a connection between a second connecting port and a second device, determining device data of the second device; and selecting one of the first and second connecting ports based on the determined device data. For example the controller may compare the charging state and/or associated available charge time of a first device and second device connected to a first and second port respectively, and may select the second port based on the comparison(s) . For example the controller may select a second port connected to a device with a lower charging state than a first device coupled to a first port.

The charging control unit of claim 4 wherein, in the event that the second connecting port is selected during the provision of the charging current to the first connecting port, the controller is configured to disconnect the charging current from the first connecting port and provide the charging current to the second connecting port.

Selecting one of the plurality of connecting ports may comprise determining a charging schedule based on the determined device data; and selecting one of the plurality of connecting ports based on the charging schedule. For example, the charging schedule may comprise a series of time slots, wherein each time slot relates to a charging period for one of the connected devices. For example the controller may select a connecting port corresponding to each time slot and provide the charging current to that connecting port for the duration of each time slot. The charging schedule may comprise an

indication of times at which the controller is connecting port.	to select	a new
The charging control	unit	may	comprise a	DC-DC	converter
configured to receive	the	charging current	from	the	AC-DC

converter and modify the voltage provided to the connecting ports. For example, the DC-DC converter may comprise a stepdown chopper, which may reduce the voltage of the charging current provided to the connecting ports.

The charging control unit of any preceding claim comprising a switch configured to disconnect the charging current from a first connecting port before the controller provides the charging current to a second connecting port. For example the controller may perform a check between disconnecting from a first connecting port and connecting to a second connecting ports, for example to ensure that there is no charge leakage from any of the connecting ports.

The devices may comprise electric vehicles and hybrid vehicles .

The controller may be configured to identify each device connected to the connecting ports; obtain from the connected devices at least one of user identification data and device identification data; and determine the charging time based on the obtained identification data.

The charging control unit may comprise a user interface, wherein the controller is configured to obtain the associated charging time from the user interface. For example the interface may comprise means, such as a touch screen or keypad, for a user to input an associated charging time, wherein the interface may be configured to provide the associated charging time to the controller.

The controller	may	be	configured to	modify	the	charging
current based on the	device data of at	least	one	connected
device .
The controller	may	be	configured to	modify	the	charging
current based on the	device data of at	least	one	connected
device .
The controller	may	be	configured to	divide	the	charging

current between a first charging current to a first connecting port, a second charging current to a second connecting port.

The controller may be configured to simultaneously provide the first charging current to the first connecting port and provide the second charging current to the second connecting port.

The proportion of the total charging current provided to the first and second charging port may be determined based on the device data associated with the at least one connected device.

The DC-DC converter may be provided by a plurality of DC-DC converters each coupled to provide a proportion of the charging current to at least a corresponding one of the connecting ports.

The plurality of connecting ports may each comprise a switch operable to modify the charging current provided through that port to a connected device.

The controller may be operable to control the proportion of the charging current provided by each of the DC-DC converters based on the device data.

The plurality of DC-DC converters may be coupled to convert DC current provided by a single AC-DC converter to supply the charging current.

A system may comprise a plurality of the charging control units, a power supply, and a controller; wherein the power supply is configured to provide a current to the charging control units; and the controller is configured to obtain a current demand from each control unit, and control the current provided to each charging control unit based on the obtained current demand.

Aspects of the invention may be provided in conjunction with each other and features of one aspect may be applied to other aspects .

Brief Description of Drawings

Embodiments of the disclosure will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 shows an environment in which a charging controller can be used for charging electric or hybrid vehicles;

Figure	2	gives	a schematic	view	of	an example	charging	control
unit ;
Figure	3	gives	a schematic	view	of	an example	charging	control
unit ;
Figure	4	shows	an environment	in	which charging controllers

can be used for charging electric or hybrid vehicles;

Specific Description

Described below with reference to Figures 1 to 4 is a charging control unit for providing charging currents to a plurality of devices. The control unit comprises an AC-DC converter which is configured to convert an AC power supply to a DC charging current. The control unit also comprises a plurality of connecting ports, where each port is configured to provide the generated charging current to one of the plurality of devices.

A controller is arranged between the converter and the connecting ports, which can determine device data, such as a charging state and/or an available charge time, for each device. Based on this information the controller can select one of the connecting ports and provide the charging current to the selected port.

One example of using such an apparatus to provide a charging current to a plurality of devices is illustrated in Figure 1. This shows a car parking facility comprising several parking bays 102, which each have a connecting port 104 for charging an electric or hybrid vehicle. Each port is electrically connected to a charging control unit 103 which is in turn electrically connected to a power supply 101. The charging control unit 103 is configured to obtain an AC current from the power supply 101 and provide a DC charging current to the ports to charge a rechargeable battery of the vehicles. The charging control unit 103 is also configured to control the current provided to each port 104.

In operation, a vehicle 105 may park in one of the bays 102 and connect to one of the connecting ports 104. The charging control 103 unit may provide a charging current to the corresponding port to charge the rechargeable electric battery 106 of the connected vehicle 105.

When more than one vehicle 105 is connected to the connecting ports 104 (as is shown in Figure 1), the charging control unit 103 may determine to which of the connecting ports to provide a charging current. For example the charging control unit 103 may obtain device data relating to each connected vehicle, such as a charging state and an available charge time of each vehicle. The charging control unit 103 can determine which connecting port to provide a charging current to, based on this obtained device data.

Figure 2 shows a schematic view of an example charging control

- 8 unit 200, for example one which could be used within the environment shown in Figure 1. The unit 200 comprises an AC-DC converter 202 electrically coupled to an external power supply 201. An electrical coupling is provided between the converter 202 and a controller 203, and the controller 203 is electrically coupled to a plurality of connecting ports 204ad. Although four connecting ports are shown in Figure 2 it will be appreciated that the charging control unit 200 may comprise any number of connecting ports.

The converter 2 02 is configured to receive an AC supply 2 01 and convert it to a DC charging current for the connecting ports. For example the converter 202 may be a rectifier comprising at least one of a vacuum tube diode, mercury-arc valve, metal-oxide rectifier, semiconductor diode, siliconcontrolled rectifier and other semiconductor switch.

The connecting ports 204 are each configured to form an electrical coupling with a device, and provide the charging current to that device. The connecting ports are also configured to enable the transfer of data, for example between a device 205 and the controller 203.

The controller 203 is configured to select one of the plurality of connecting ports 204, and provide the charging current to the selected port (for example the port 204a). The controller 203 is also configured to obtain device data and select a port based on the obtained data. For example the controller may obtain device data from the device 205 coupled to a connecting port 204a, and/or a user interface. The controller 203 may comprise a switch that is operable to connect and disconnect the charging current to and from each of the connecting ports 204a-d. The switch is configured to disconnect from a first connecting port before providing a connection to a second connecting port.

In Figure 2 the charging control unit also comprises a DC-DC converter 2 07 coupled to the AC-DC converter 2 02 and the controller 203. The DC-DC converter 207 receives the DC current from the AC-DC converter 202 and modifies the voltage of the charging current provided to the connecting ports 204. For example the DC-DC converter may comprise a step-down chopper for reducing the DC charging current from the AC-DC converter 202 that is provided to the connecting ports.

In operation when a device 2 05 couples to one of the ports 204, the controller detects that a connection has been made. For example, a signal may be obtained by the controller 2 03 from a port (e.g. 204a) indicating that a connection has been made between the port 204a and the device 205. In response the controller 203 may select the port 204a and provide the charging current from the converter 202 to the port 204a.

The controller 203 may provide a request to the connected device 205, via the port 204a, requesting further device data to be provided to the controller 203. For example the controller 203 may request data relating to a rechargeable battery within the device 205, such as an associated charging state. The associated charging state may comprise an indication of energy stored in the battery as a proportion of the total capacity of the battery. In response to the request from the controller 203 the connected device 205 may provide device data, such as the associated charging state of its battery to the controller 203. The controller 203 may thereby determine the associated charging state of the connected device 205.

A second device 206 may connect to a second port 204d while the first device 205 is connected to the first port 204a. The controller 203 can communicate with the second device 206 and request and obtain data in the same way as described for the first device 205. The controller 203 can therefore determine the associated charging states for a plurality of connected devices 205, 206, and select one of the connecting ports 204a, ίο

204d based on the determined charging state of the connected devices 205, 206. The controller 203 can then provide the charging current to the selected connecting port.

In one example the controller 2 03 may determine that the rechargeable battery of the first device has an energy level above a particular threshold percentage, and may also determine that the battery of the second device has an energy level below the threshold percentage. For example the threshold percentage may be 80% of the battery capacity. Based on this, the controller 203 may select the second connecting port 2 04d and provide the charging current to this port to charge the rechargeable battery of the second device 206. For example, if the second device is coupled to the second port 204d while the charging control unit 200 is already charging the first device, the controller may disconnect the charging current from the first port 204a, and provide it to the selected second port 204d.

In another example the batteries of both devices 205, 206 may have an energy level below the threshold percentage. If the second device is coupled to the second port 204d while the charging control unit 200 is charging the first device 205, the controller may continue to charge the first device until its battery reaches the threshold percentage. The controller 2 03 may determine that the first battery has reached the threshold percentage and, in response, the controller may disconnect the charging current to the first port 204a, and provide it to the selected second port 204d to charge the rechargeable battery of the second device 206.

In another example the controller may determine the charging state of a plurality connected devices, and may also determine the available charge time of at least one of the connected devices. The controller may then select one of the connecting ports to provide the charging current to, based on both the associated charging state and available charge times of the connected devices. For example the available charge time of a device may be provided to the controller via a user interface.

Figure 3 illustrates a schematic view of an example charging control unit 300. A controller 301 is electrically coupled to a converter and a plurality of connecting ports, for example as shown in Figures 2 or 3. The controller 301 is also electrically coupled to a data store 302. An example port 303 is shown coupled to a device 305 for charging that device. The port 303 is also coupled a user interface 304. It will be appreciated that although Figure 3 shows the port 303 and the user interface 304 as separate components, the user interface may be integrated into the connecting port. The user interface 304 is configured to obtain user identification data and provide it to the controller 301.

The data store 302 is configured to store identification data - such as device identification data and user identification data - and associated available charging time data, wherein each item of identification data has an available charging time associated with it. For example the identification data and associated charging time data may be stored in a look-up table. The associated charging time may be an estimated time that the device 3 05 connected to the port 3 03 has available for charging. For example the estimated time may be set externally by the user prior to coupling the device 305 to the port 303, wherein setting this time updates the table stored in the data store 302.

In one example an estimated time may be set over a wide area network by a user using a portable and/or hand-held device such as a smartphone. The charging control unit may be configured to communicate with smartphones and similar user equipment, via an external server for example, over a widearea network such as the internet. For example, after a connection between is detected between a device and a connecting port, a user may input the estimated time via a user interface of a handheld device, and based on the inputted time, the handheld device may provide charging time data over the wide-area network to the charging control unit.

User identification data may be stored on a portable and/or hand-held device such as a smartphone, and the charging control unit may be configured to obtain the user identification data from such a device. For example the charging control unit may comprise a near field communication (NFC) interface operable to communicate with smartphones and other NFC enabled devices, to obtain the user identification data from the device and provide it to the controller. Other objects and devices may be configured to store user identification data on a radio frequency identification (RFID) tag, and the charging control unit may comprise an RFID reader, operable to obtain the user identification data from the RFID objects/devices and provide it to the controller. The charging control unit may comprise a Wi-fi (RTM) interface configured to obtain user identification data stored on a device such as a smartphone over a Wi-fi (RTM) network, and provide it to the controller. The charging control unit may comprise a Bluetooth (RTM) interface to obtain user identification data stored on a device over a Bluetooth (RTM) network .

User identification data may be stored on a personal card such as a supermarket loyalty card. For example the user identification data may be stored as a barcode on the card and the user interface may comprise a barcode scanner to read the barcode and provide the user identification data to the controller 301.

User identification data may also be obtained from a payment card. For example the user identification data may be stored on the card and a payment terminal configured to communicate with the charging control unit may obtain the user identification data from the card in the event that the card is presented to the payment terminal. The controller of the charging control unit may then obtain the user identification data from the payment terminal.

Alternatively or in addition, the controller 301 may also be configured to obtain vehicle identification data from the device 305 via the connecting port 303. For example, in the event of a connection between a port 3 03 and a device 3 05, vehicle identification data may be provided automatically to the controller 301. Alternatively the controller 301 may provide a request to the device 305 to provide the vehicle identification data, and the device 305 may provide the vehicle identification data to the controller 301 in response.

In one example, in which the devices are electric vehicles, identification data may be determined by an automatic number plate recognition (ANPR) system. For example, the ANPR system may read the number plate of a vehicle as it approaches a connecting port, and may access a database to identify the vehicle based on its number plate. The charging control unit may be configured to communicate with the ANPR system such that the controller can obtain the device identification data from the ANPR system.

Alternatively the available charge time that is stored in the data store 3 02 for a device may be based on the average charging time for the device, from previous charging of the device by a charging unit.

In response to obtaining user identification data from the user interface, the controller obtains the charging time data associated with that user identification data from the data store 302. The controller 301 can therefore determine an associated charging time for the connected device 305.

In another example an available charge time for a connected device 3 05 can be directly obtained from the user interface

304. For example the user interface may comprise an interface, such as a touch screen or keypad, to enable a user to directly provide the time that the connected device 3 05 has available to charge. This available charge time can be provided to the controller 301. Thus, the controller 301 can determine the available charge time of the connected device 305 based on the input from the user interface 3 04, and use this to select a connecting port to provide a charging current to.

The controller 301 is configured to select a connecting port (to provide a charging current to) based on the determined charging time of the device.

In operation, while the charging current is being provided to a first device via a first connecting port, a second device may couple to a second connecting port. The controller may determine the available charging time of the second device as described above. In one example the controller may determine that the available charging time of the second device is less than the available charging time of the first device. In response the controller may disconnect the charging current from the first connecting port and provide the charging current to the second connecting port.

In one example the controller may determine the available charging time of the first and second devices as described above, and also determine the charging state of the first and second devices, for example as described with reference to Figure 2. The controller may select the second connecting port based on both the charging state and available charging state of the devices.

In an example in which multiple devices connect to the charging control unit, the controller may determine a charging schedule based on the determined device data, that is, the charging states and/or available charge times of the connected devices. For example the schedule may comprise an indication of when and/or for how long the control unit should charge each device. The controller may then select connecting ports to provide the charging current to, based on this schedule. Such a charging schedule can include a series of time slots for example, where each time slot relates to a charging period for one of the connected devices. The controller can therefore select the corresponding connecting port to provide the charging current to for the duration of each time slot.

Figure 4 illustrates a system comprising a plurality of charging control units 401, 402 such as those described with reference to Figures 2 and 3. Although two charging control units are shown, it will be appreciated that the system could comprise many more than this. Each control unit is coupled to a plurality of connecting ports 403a-d, 404a-d, which are available for electrically coupling to devices. The system comprises a power supply 406 configured to provide an AC power supply to a controller 405. The controller is coupled to the plurality of charging control units and is configured to provide the control units with an AC power supply to them. The controller is also configured to obtain a current demand from the charging control units 401, 402. For example, as shown in Figure 4, a first charging control unit 401 may have a greater number of ports coupled to a device for charging than a second control unit 402. Therefore the current demand for the first control unit may be greater than for the second control unit 402. The control units 401, 402 provide current demand data to the controller 405, and in response the controller 405 may control the current provided from the power supply 406 to each charging control unit based on the obtained current demand. For example the controller may provide a greater current to the first control unit 401 than the second control unit 402 as the current demand of the first control unit 401 is greater than the second control unit 402.

Alternatively the current provided by the power supply 406 may be divided evenly between the control units 401, 402 by the illustrates a system in which a controller for current to a plurality an AC-DC converter. In controller 405.

Figure 5 providing comprises controller

505 comprises converter is coupled control units 501a,b.

an AC-DC of charging control units the Figure 5 system, a converter 504. The AC-DC to a power supply 506 and a plurality

AC-DC converter 504 is configured from power supply 506 to a DC supply

The of to convert an AC supply be provided to the control units 501a,b. The control units 501a,b may then provide a DC charging current their respective connecting ports, for example via the controllers 502a,b as described above with reference to the previous drawings. The control units 501a,b may each comprise a DC-DC converter to

503a,b such as a step down chopper, to modify the DC charging current provided to the connecting ports which in turn are configured to provide the DC charging current from their respective control unit to a connected device.

It will be appreciated that systems with other arrangements to those shown in Figures 4 and 5 are possible. For example a system may comprise a plurality of controllers coupled to an AC power supply and configured to convert the AC supply to a DC supply. Each controller may be coupled to a plurality of control units or to a single control unit. Each control unit may comprise a DC/DC converter to control or modify the DC charging current provided to the connecting ports. Furthermore, each control unit may be coupled to a plurality of connecting ports, or to a single connecting port. For example a separate control unit may be coupled to each connecting port.

A charging control unit may be configured so that a charging current is provided from more than one connecting port to more than one connected device simultaneously. Furthermore a control unit may enable differential and/or incremental charging to each of the connected devices. A controller may be configured to modify the charging current based on the device data of at least one connected device, for example by dividing the total charging current between a first charging current to a first connecting port, a second charging current to a second connecting port.

A control unit may comprise a plurality of DC-DC converters configured to modify the charging current, such that different connecting ports are able to provide different charging currents to connected devices. Figure 6 illustrates a charging control unit 600 in which a controller 603 obtains a DC supply from an AC-DC converter 202 and provides it to a plurality of connecting ports 604a-d for charging one or more connected devices. A set of DC-DC converters 607a-d is provided between the controller 603 and each connecting port 604a-d. The DC-DC converters 607a-d are configured to modify the charging current received from the controller. Each DC-DC converter may be configured to modify the charging current received from the controller by a different amount. For example, a greater charging current may be provided to a second connecting port for a second device, than to a first connecting port for a first device. For example, a controller may provide instructions to a DC-DC converter to modify its output current, based on the device data of at least one connected device (which may be obtained as described above) . In some examples the set of DC-DC converters are provided within or as part of their corresponding connecting port.

A controller may provide instructions to each DC-DC controller to modify the charging current provided to each connected vehicle. The instructions may be based on the device data of each connected device. As just one example, if a first connecting port is providing a charging current to a first device, the controller may determine that the rechargeable battery of the first device has reached an energy level above a particular threshold percentage, such as 80% of the battery capacity. If a second device is coupled to a second connecting port, the controller may, in response to determining that the first device has reached the threshold, provide a charging current to the second connecting port but continue to provide a charging current, lower than the initial charging current, to the first connecting port.

With reference to the drawings in general, it will be appreciated that schematic functional block diagrams are used to indicate functionality of systems and apparatus described herein. It will be appreciated however that the functionality need not be divided in this way, and should not be taken to imply any particular structure of hardware other than that described and claimed below. The function of one or more of the elements shown in the drawings may be further subdivided, and/or distributed throughout apparatus of the disclosure. In some embodiments the function of one or more elements shown in the drawings may be integrated into a single functional unit.

In some examples, one or more memory elements can store data and/or program instructions used to implement the operations described herein. Embodiments of the disclosure provide computer program products such as machine readable instructions and/or tangible, non-transitory storage media comprising program instructions operable to program a processor to perform any one or more of the methods described and/or claimed herein and/or to provide data processing apparatus as described and/or claimed herein.

The activities and apparatus outlined herein may be implemented using controllers and/or processors which may be provided by programmable instructions fixed logic logic such executed or programmable programmable logic digital logic such as assemblies of logic gates as software and/or computer program by a processor. Other kinds of include programmable processors, (e.g., a field programmable gate array (FPGA), an erasable programmable read only memory (EPROM), an electrically erasable programmable read only memory (EEPROM)), an application specific integrated circuit, ASIC, or any other kind of digital logic, software, code, electronic instructions, flash memory, optical disks, CD-ROMs, DVD ROMs, magnetic or optical cards, other types of machinereadable mediums suitable for storing electronic instructions, or any suitable combination thereof.

The above embodiments are to be understood as illustrative examples. Further embodiments are envisaged. It is to be understood that any feature described in relation to any one embodiment may be used alone, or in combination with other features described, and may also be used in combination with one or more features of any other of the embodiments, or any combination of any other of the embodiments. Furthermore, equivalents and modifications not described above may also be employed without departing from the scope of the invention, which is defined in the accompanying claims.

Other variations and modifications of the apparatus will be apparent to persons of skill in the art in the context of the present disclosure.

Claims

1. A charging control unit for providing charging currents to a plurality of devices, to charge rechargeable electric batteries in said devices, the control unit comprising :

an AC-DC converter configured to convert an AC power supply to a DC charging current;

a plurality of connecting ports wherein each port is configured to provide the charging current to a corresponding one of the plurality of devices;

a controller, arranged between the converter and the plurality of connecting ports, wherein the controller is configured to:

determine for each device, device data comprising at least one of :

a) a charging state of that device; and

b) an available charge time of that device; select one of the plurality of connecting ports based on the device data; and provide the charging current to the selected connecting port.

2. The charging control unit of claim 1 wherein each rechargeable electric battery has an energy storage capacity, and the charging state comprises an indication of energy stored in the battery as a proportion of the energy storage capacity.

3 . The charging control unit of any preceding claim wherein the controller is configured so that, in the event of a first device connecting to a first connecting port, the controller is configured to determine device data of the first device.

4. The charging control unit of claim 3 wherein selecting one of the plurality of connecting ports comprises, in the event of a connection between a second connecting port and a second device, determining device data of the second device; and selecting one of the first and second connecting ports based on the determined device data.

5. The charging control unit of claim 4 wherein, in the event that the second connecting port is selected during the provision of the charging current to the first connecting port, the controller is configured to disconnect the charging current from the first connecting port and provide the charging current to the second connecting port.

The charging control selecting comprises determined unit of claim 1 or 2 wherein plurality schedule .

plurality of connecting determining a charging schedule device data;

of connecting one of the ports based on the and selecting ports based on one the of the charging

7. The charging control unit of claim 6 wherein the charging schedule comprises an indication of times at which the controller is to select a new connecting port.

8. The charging control unit of any preceding claim comprising a DC-DC converter configured to receive the charging current from the AC-DC converter and modify the voltage provided to the connecting ports.

9. The charging control unit of claim 8 wherein the DC-DC converter comprises a step-down chopper.

10. The charging control unit of any preceding claim comprising a switch configured to disconnect the charging current from a first connecting port before the controller provides the charging current to a second connecting port.

The charging control unit of any preceding claim wherein the devices are electric or hybrid vehicles The charging control unit of any preceding claim,

wherein the controller is configured to identify each device connected to the connecting ports; obtain from the connected devices at least one of:

user identification data; and device identification data;

and determine the charging time based on the obtained identification data.

13 . The charging control unit of any preceding claim, comprising a user interface, wherein the controller is configured to obtain the associated charging time from the user interface.

14 . The charging control unit of any preceding claim, wherein the controller is configured to modify the charging current based on the device data of at least one connected device.

15. The charging control unit of claim 14, wherein the controller is configured to divide the charging current between a first charging current to a first connecting port, a second charging current to a second connecting port.

16 . The charging control unit of claim 15 wherein the controller is configured to simultaneously provide the first charging current to the first connecting port and provide the second charging current to the second connecting port.

17. The charging control unit of claim 15 or 16 wherein the proportion of the total charging current provided to the first and second charging port is determined based on

the device data connected device. associated with the at least one 18 . The charging control unit of claim 8 or any claims dependent thereon , wherein the DC-DC converter is

provided by a plurality of DC-DC converters each coupled to provide a proportion of the charging current to at least a corresponding one of the connecting ports.

19. The charging control unit of claim 18 wherein the plurality of connecting ports each comprise a switch operable to modify the charging current provided through that port to a connected device.

20. The charging control unit of claim 18 or 19 wherein the controller is operable to control the proportion of the charging current provided by each of the DC-DC converters based on the device data.

21. The charging control unit of any of claims 18 to 20 wherein the plurality of DC-DC converters are coupled to convert DC current provided by a single AC-DC converter to supply the charging current.

22. A system comprising a plurality of the charging control units of any preceding claim, a power supply, and a controller;

wherein the power supply is configured to provide a current to the charging control units; and the controller is configured to:

obtain a current demand from each control unit; and control the current provided to each charging control unit based on the obtained current demand.

23 . A method of controlling charging currents to a plurality of devices for charging rechargeable electric batteries in said devices, the method comprising: determining device data comprising at least one of:

a) a charging state of that device; and

b) an available charge time of that device; selecting one of the plurality of connecting ports based on the device data; and providing the charging current to the selected connecting port.

24. The method of claim 23 wherein each rechargeable electric battery has an energy storage capacity, and the charging state comprises an indication of energy stored in the battery as a proportion of the capacity.

25. The method of claim 23 or 24 comprising determining, in the event of a connection between a first connecting port and a first device, device data of the first device.

plurality of connecting ports comprises, in the event of determining

27. The method of claim 26 comprising, in the event that the second connecting port is selected during the provision of the charging current to the first connecting port, disconnecting the charging current from the first connecting port and providing the charging current to the second connecting port.

28. The method of claim 23 or 24 wherein selecting one of the plurality of connecting ports comprises determining a charging schedule based on the determined device data; and selecting one of the plurality of connecting ports based on the charging schedule.

29. The method of claim 28 wherein the charging schedule comprises an indication of times at which the controller is to select a new connecting port.

30. The method of any of claims 23 to 29 wherein a DC-DC converter is configured to receive the charging current from the AC-DC converter and modify the voltage provided to the connecting ports.

31. The method of claim 30 wherein the DC-DC converter comprises a step-down chopper.

32. The method of any of claims 23 to 31 comprising a switch configured to disconnect the charging current from a first connecting port before providing the charging current to a second connecting port.

33 . The method of any of claims 23 to 32 wherein the devices are electric or hybrid vehicles.

34. The method of any of claims 23 to 33, comprising identifying each device connected to the connecting ports; obtaining from the connected devices at least one of :

user identification data; and device identification data;

and determining the charging time based on the obtained identification data.

35. The method of any of claims 23 to 34 comprising a user interface, and wherein the method comprises obtaining the associated charging time from the user interface .

36 The method of any of claims 23 to 35, comprising modifying the charging current based on the device data of at least one connected device. 37 The method of any of claims 23 to 36, comprising

dividing the charging current between a first charging current to a first connecting port, a second charging current to a second connecting port.

38. The method of claim 37 wherein comprising simultaneously providing the first charging current to the first connecting port and provide the second charging current to the second connecting port.

39. The method of claim 37 or 38 wherein the proportion of the total charging current provided to the first and second charging port is determined based on the device data associated with the at least one connected device.

40. The method of any of claim 30 or any claims dependent thereon, wherein the DC-DC converter is provided by a plurality of DC-DC converters each coupled to provide a proportion of the charging current to at least a corresponding one of the connecting ports.

41. The method of claim 40 wherein the plurality of connecting ports each comprise a switch operable to modify the charging current provided through that port to a connected device.

42. The method of claim 40 or 41 comprising controlling the proportion of the charging current provided by each of the DC-DC converters based on the device data.

43. The method of any of claims 40 to 42 wherein the plurality of DC-DC converters are coupled to convert DC

- 27 current provided by a single AC-DC converter to supply the charging current.