GB2525068A

GB2525068A - Transportable charging station

Info

Publication number: GB2525068A
Application number: GB1501886.4A
Authority: GB
Inventors: Timothy Peter Martin
Original assignee: Zapinamo Ltd
Current assignee: Zapinamo Ltd
Priority date: 2014-02-04
Filing date: 2015-02-04
Publication date: 2015-10-14
Also published as: GB201401847D0; GB201501886D0

Abstract

A transportable, or portable, charging station 101 comprises a battery of rechargeable storage cells 102 which are charged from an input supply 105 at an input power /rate P1 and which are discharged at an output power/rate to charge electrical storage cells 104 of an electric vehicle, wherein the output power/rate P2 is greater than the input power/rate P1. A data storage device is used to store a data record that is created for each vehicle charging operation. An input converter receives electrical energy at an input power level P1 while an output converter supplies electrical energy at a plurality of selectable output power levels (e.g. charging modes 1-4), each output power level P2 being higher than the input power level P1. The charging station 101 may be housed within a transportable cabin, a mobile trailer or a vehicle. The data record may: identify the rate of discharge; record locations at which the discharging operation takes place; and/or create a dataset to facilitate analysis of charging data, from which permanent charging posts are established in response to the analysis.

Description

Transportable Charging Station The present invention relates to a transportable charging station for an electric vehicle.

Charging stations for electric vehicles are known, capable of providing high voltage direct current to achieve rapid charging. In addition, it is also known to charge vehicles from standard mains supplies. Standard mains supplies have an advantage in that they are widely available. However, they are not capable of providing high levels on charge and therefore usually require the vehicle to be left on charge overnight. For some vehicles currently in production, an overnight charge from a standard mains supply may not fully recharge the battery.

A known problem relating to the use of electric vehicles is that of range anxiety'. Thus, for many journeys, sufficient energy may be available to make the journey successfully. However, some motorists are reluctant to is adopt electric vehicles given that, should the batteries become fully discharged, little provisions exists for the batteries to be recharged at remote locations and, in particular, recharged at a relatively high rate.

* ** As the number of electric vehicles increases, greater provision will be made for charging operations to be performed. However, it is currently also * 20 accepted that problems exist in terms of locating charging stations where they are most useful and problems also exist in terms of identifying where the most useful locations would be.

According to an aspect of the present invention, there is provided a transportable charging station for an electric vehicle, comprising: a battery of *:.* 25 rechargeable cells; an input converter for receiving electrical energy at an * input power level; an output converter for supplying electrical energy at a plurality of selectable output power levels, wherein each of said output power levels is higher than said input power level; and a data storage device for creating a data record for each instance of a vehicle being charged.

The charging station may be housed within a transportable cabin, a mobile trailer or within a vehicle.

In an embodiment, input power is received from a conventional mains supply.

The output level may include a low level compatible with low level charging, not greatly above the input level. The charging station may also provide output power levels that include a medium level compatible with the highest available level of charging currently implemented.

The charging station may also be in a position to provide output power levels that are higher than any currently achievable implementations.

The invention will now be described as a way of example only, with reference to the accompanying drawings; of which: Figure 1 shows a schematic representation of a transportable charging environment; Figure 2 shows a charging station implemented as a transportable cabin; Figure 3 shows a charging station housed within a mobile trailer and housed within a motor vehicle; Figure 4 illustrates details of a transportable charging station; * .* Figure 5 shows operations performed by the charging station in order :.: to generate data records; and * 20 Figure 6 illustrates an example of a data record. 0* * * S S * S.

Figure 1 A schematic representation of a transportable charging environment : for charging an electric vehicle is illustrated in Figure 1. A portable charging station 101 includes electrical storage cells 102. Similarly, a vehicle 103 includes electrical storage cells 104. When the vehicle 103 is recharged from the portable charging station 101, a significant level of power, indicated as P2, may transfer from the storage cells 102 of the portable charging station 101 to the storage cells 104 of the vehicle 103. Transfers of this type usually take place using direct current to avoid making use of rectification devices within the vehicle.

The transfer of energy from the portable charging station to the vehicle is not dependent upon the rate at which this energy is received by the portable charging station from an energy source 105. This power transfer is identified as P1. In an embodiment, an electrical input may be received from a rectified mains supply. This may be considered as a trickle' charge. In alternative embodiments, the rate of energy transfer may be increased during off-peak periods but, in an embodiment, the specifications of this supply are of a substantially standard nature of the type currently available for domestic implementation. Energy could also be received from a renewable source, such as a solar panel.

An advantage of the portable charging station of this embodiment is that it allows high rates of transfer to take place in locations where a charging post designed for this purpose is not available. It also allows the charging station to be made available immediately at substantially any location, thereby decoupling the functionality of charging a vehicle from the underlying charging functionality of the energy source.

In addition, the portable charging station allows charge to be received * .* at full power at any time during the day. Thus, in situations where the device :.: makes use of off-peak electricity, it is still possible for the charge to be * 20 received by vehicles during times of peak demand. Thus, there is a temporal decoupling in terms of when the charge is received from the grid and when the charge is delivered to the vehicle.

F!gure2 In an embodiment, the charging station 101 is housed within a transportable cabin 201. The cabin 201 may be located upon a conventional parking space so as to allow a first vehicle 202 to be charged when located in a first adjacent parking location and a second vehicle 203 to be charged when located in the opposite adjacent parking location. Facilities may be provided within the transportable cabin for refreshments to be served, for example, while the charging process takes place.

In this embodiment, it is possible for a high power transfer to take place (a P2 transfer) over a first connector 204 to vehicle 202 while at the same time providing a high level of charge to vehicle 203 via a similar connector 205.

Figure 3 In an alternative embodiment, the portable charging station 101 is housed within a mobile trailer 301. The cabin of Figure 2 may be designed to remain at a location for several months and is possibly semi-permanent.

However, an advantage of the portable charging station is that it allows for data to be collected to facilitate planning processes for deciding where permanently located charging posts should be positioned.

In some applications, a portable charging station may be required, to move more frequently. Thus, for example, the charging functionality could be provided at a specific location for a number of weeks.

In a third embodiment, the charging station is located within a vehicle 302. Thus, with the vehicle implementation, an even greater level of portability is provided and operational periods could be reduced to a number of days. A vehicle of this type could also be provided for a special event, * where a promoter is looking to support the use of electric vehicles. * * * *

Figure 4 An example of a transportable charging station for an electric vehicle : is illustrated in Figure 4. A charging station includes a battery 401 of rechargeable cells. In addition, there is provided an input converter 402 for receiving electrical energy at an input powerievel from input terminals 403.

An output converter 404 supplies electrical energy at a plurality of selectable output power levels at output terminals 405, 406, 407 and 408.

Each of the output power levels is higher than the input power level. The equipment is also provided with a data storage device 409 for creating a data record for each instance of a vehicle being charged.

In the embodiment of Figure 4, the station also includes a data transmission device 401 for transmitting recorded data to a central control station. This allows the operation of portable charging stations in the field to be monitored and maintained. Furthermore, it also facilitates the collection of historical use data to facilitate the planning and redeployment of portable charging stations, along with the planning and deployment of permanent charging posts.

The international electro-technical commission (IEC) has established charging modes that are now implemented by a number of commercially available connector configurations.

Under the established standard, mode 1 provides for slow charging from a household type socket outlet with mode 2 being an improvement over this, in that an additional in-cable protection device is included. In mode 1, current is limited to 16 amps at 250 volts AC.

Mode 2 of the standard also involves the connection of the vehicle to a standard AC mains socket outlet using a dedicated cable that has a built in control box. Thus, in an embodiment, output connector 405 may be of the * ** mode 2 type providing 32 amps, representing a relatively low charge rate but still greater than the supply provided to the portable charging station, which * 20 may receive power from a domestic supply only capable of delivering 13

amps for example.

In an embodiment, output connector 406 may be of the mode 3 type in which connectors have control and signal pins. This ensures that the charging station socket is not live when it is not connected to an electric vehicle. Mode 3 operation provides for a higher rate of charge but still using alternating current such that in-car rectification is required.

Output terminal 407 may be identified as a mode 4 type allowing the electric vehicle to receive direct current. Output 408 may also be of the mode 4 type and in an embodiment, given the nature of the energy source, mode 4 DC charging optimises the available resources. Typical currents in mode 4 are up to 400 amps although, in an embodiment, it is possible that higher currents could be achievable so as to incorporate a degree of future proofing.

Thus, in an embodiment, the power transfer to the vehicle would be limited by the capabilities of the vehicle not the charger.

It is also known for connections of this type to include data connections; with the charging station interfacing with the CAN (controller area network) bus resident within the vehicle. By performing handshaking operations via the CAN bus protocol, it is possible for the charging station to perform a safety interlock to avoid energising the connector before it is safe to do so. Furthermore, battery parameters such as when to stop charging, a preferred final voltage and total battery capacity may be relayed back to the portable charging station. All of this data may be collected by the data storage device 409 to facilitate later analysis.

Thus, in an embodiment, output connector 405 may be a low level output that is not greatly above that of the input level. Output connector 406 may be considered to provide a medium output level and this medium level may be compatible with the highest currently available level of charging actually implemented by a vehicle. In an embodiment, output 408 may * ** provide an output power at a very high level; higher than any currently achievable implementation, so as to be ready for future implementations S.....

* 20 without major modification. Such an approach also ensures that, during most recharging operations, the battery 401 will provide a high level of power while still operating comfortably within i!s full capabilities.

In the embodiment of Figure 4, the battery 401 includes groups 411, *5*e : 412, 413 and 414 of cells connected in parallel. Within each group, such as group 111, there are a plurality of cells 415,416 connected in series.

The portable charging station includes a plurality of relays 417, 418, 419 and 420. These relays allow cell groups 411 to 414 to be selected for connection to the input converter 402 and cell groups to be selected for connection to the output converter 404.

The input converter 402 includes a rectifier for rectifying input alternating current so as to provide direct current for charging the cells 415, 416 etc. Converter 404 receives current from the battery 401 and is some implementations may include an inverter for producing an alternating output, at terminal 405, primarily for compatibility purposes.

In addition, direct current outputs are provided as disclosed, using DC to DC conversion circuitry, as is known in the art.

Operation of the power conversations is overseen by a control processor 421. Control processor 421 controls the operation of relays 417 to 420 and the operation of input converter 402 and the operation of output converter 404.

Processor 421 is also responsible for interfacing with the resident CAN bus of vehicle being charged and for collecting information about the charging process in order to create a data record.

Figure 5 An example of operations performed by processor 421 are illustrated in Figure 5.

After initiating the system at step 501, recharging at a low rate via input converter 402, occurs at step 502.

At step 503 a question is asked as to whether an external vehicle has made a request to be charged and if answered in the negative, recharging continues at step 502.

If the question asked at step 503 is answered in the affirmative, to the n effect that a vehicle is waiting to be charged, an indication of the power rating of the vehicle is received at step 504.

The power rating may be specified manually or relevant information may be received via the CAN bus protocol. In an embodiment, the system will attempt to deliver power at the highest possible rate, so as to minimise the charging duration. Thus, at step 505 the charge is delivered via the output converter 404. Charge will continue to be delivered in accordance with the charging schedule established from data received from the vehicle. In an embodiment, it is possible that fast charging will occur initially, whereafter the rate of charge will be reduced in a way that is sympathetic to the preferences of the battery resident within the vehicle, such as vehicle 203.

At step 506, a questions is asked at to whether the charge is to stop and when answered in the negative charge delivery continues at step 505.

When the question asked at step 506 is answered in the affirmative, to the effect that the charging should stop, the charging operation ceases and the charging cable, such as cable 205, is isolated from the electrical supply, thereby facilitating safe removal.

At step 507 a data record is created and written to the data storage device 409.

At step 508 a question is asked as to whether the battery 401 is to be recharged and when answered in the affirmative, the recharging operation is repeated at step 502.

Thus, in an embodiment, the portable charging station will always attempt to recharge battery 401 after a discharge has occurred. It follows the philosophy of attempting to deliver maximum charge at the fastest possible * ** rate to recharging vehicles while at the same time always attempting to : recharge itself when not in use.

**.**.

* 20 It is also appreciated that the charging station is transportable *: therefore at the end of a charging session, the question asked at step 508 may be answered in the negative to facilitate a shutdown as indicated at step 509. * . *

Figure 6 An example of a data record 601 created at step 507 is illustrated in Figure 6.

A unique record number is entered at 602 and at 603 a charge type is recorded. Thus, in an embodiment, the charge type will be defined by the particular output terminal 405 to 408 used to perform the charging operation.

At 604 the start time of the charging operation is recorded followed by the end time at 605. Alternatively, it is possible to record a duration of charge and is also possible for that duration to identify points at which the rate of charge was modified as previously described.

By receiving data from the CAN bus of the vehicle, it is possible to identify the condition of the battery 606 before the charging was initiated and for the condition to be again recorded at 607 after the charging operation.

An advantage of the portable charging station is that it can be moved to different positions to allow data to be collected so as to provide intelligence for planning charging networks. Thus, data identifying the location of the charging station is recorded at 608. This data may be recorded manually by inputting details of a postcode for example. Alternatively, the portable charging station may include a satellite navigation system thereby allowing the location data to be collected automatically for recordal at 608. * ,* * * . *. .

* *0** * * *. . * * * * S. * .. *s * * r

Claims

Claims 1. A transportable charging station for an electric vehicle, comprising: a battery of re-chargeable cells; an input converter for receiving electrical energy at an input power level; an output converter for supplying electrical energy at a plurality of selectable output power levels, wherein each of said output power levels is higher than said input power level; and a data storage device for creating a data record for each instance of a vehicle being charged.
2. The charging station of claim 1, housed within a transportable cabin.
3. The charging station of claim 1, housed within a mobile trailer.

:
4. The charging station of claim 1, located within a vehicle.
5. The charging station of any of claims 1 to4, wherein: *:fr*. input power is received from a conventional mains supply.
6. The charging station of any of claims I to 5, wherein said output power levels include a low level compatible with low level charging, not greatly above the input level.
7. The charging station of any of claims 1 to 6, wherein said output power levels include a medium level compatible with the highest available level of charging currently implemented.
8. The charging station of any of claims 1 to 7, wherein said output power levels include a future-proofing very high level, higher than any currently achievable implementation.
9. The charging station of any of claims 1 to 8, wherein said battery includes groups of cells connected in parallel, wherein each said cell group includes a plurality of cells connected in series.
10. The charging station of claim 9, including a plurality of switches for selecting cell groups for connection to said input converter and for selecting cell groups for connection to said output converter.
11. A method of charging electric vehicles, comprising the steps of: configuring a transportable charging station at a candidate location with an input supply of electrical energy; charging a battery of re-chargeable cells from said input supply of electrical energy via at an input rate; discharging said battery of re-chargeable cells in order to charge an electric vehicle at an output rate, wherein said output rate is greater than said input rate; creating a data record for each charging operation; and resuming said charging step substantially after said discharging step has been completed.
12. The method of claim 11, wherein said data record identifies the **.* * 25 rate of discharge. * S
13. The method of claim 11 or claim 12, further comprising the step of recording locations at which said discharging operation takes place.
14. The method of claim 13, further comprising the step of creating a data-set to facilitate an analysis of charging data.
15. The method of claim 14, wherein permanent charging posts are located in response to said analysis.
16. Transportable charging station substantially as herein described with reference to Figures 1 to 4.
17. A method of charging electric vehicles substantially as herein described with reference to Figures 5 and 6. * .* * * . ** * * **** * * ** * * * . * ** * *** * * * ** * * * *