GB2536242A

GB2536242A - A charge controller

Info

Publication number: GB2536242A
Application number: GB1503992.8A
Authority: GB
Inventors: Edward Foster Simon; Edgar David
Original assignee: Intelligent Energy Ltd
Current assignee: Intelligent Energy Ltd
Priority date: 2015-03-09
Filing date: 2015-03-09
Publication date: 2016-09-14
Also published as: GB201503992D0

Abstract

A charging system 100 comprises an energy supply 104 and a charge controller 106,108 configured to determine a charging parameter for an electronic device 102 based on a charge end time and cause the energy supply 104 to provide power to the device 102 in accordance with the charging parameter. The charge controller is also configured to automatically cause the energy supply to charge the electronic device in response to the charge level of the device falling below a low-charge threshold value. The charging parameter may comprise a charging start time. The controller may determine a charging start time based on a charging profile such that the device has a target charge level at the charging end time. The charging parameter may be determined based on an energy usage profile and may be periodically recalculated. The energy supply 104 may comprise a fuel cell system. The controller may transmit a start-up signal to the energy supply at or in advance of the charging start time. The controller may receive a charging end time from alarm application software and may receive a target charge level and/or charging end time from a user interface.

Description

A Charge Controller The present disclosure relates to a charge controller for determining a charging parameter of a charging event for an electronic device.

According to a first aspect of the invention, there is provided a charge controller configured to determine a charging parameter for an electronic device based on a charging end time.

Such a charge controller can advantageously enable more efficient charging of an electronic device because the electronic device may not need to be in a trickle charge mode of operation for a long time after the electronic device has been fully charged.

The charging parameter may comprise a charging start time. The charge controller may be configured to determine the charging start time based on a charging profile such that the electronic device has a target charge level at the charging end time.

The charge controller may be configured to determine a charging parameter for an electronic device based on a target charge level at the charging end time. The charge controller may be configured to determine the charging event parameter for the electronic device based on a charging profile for the electronic device. The charge controller may be configured to determine the charging parameter based on an energy usage profile.

The charge controller may be configured to periodically recalculate the charging parameter. The charge controller may be configured to selectively, based on a charge level of the electronic device, recalculate the charging parameter. The charge controller may be configured to selectively, based on the determined charging parameter, recalculate the charging parameter.

The charge controller may be configured to transmit a start-up signal to an energy supply in accordance with the charging start time.

The energy supply may comprise a fuel cell system. The controller may be configured to transmit the start-up signal to the energy supply at the charging start time. The controller may be configured to transmit the start-up signal to the energy supply in advance of the charging start time, such that the energy supply will start providing energy at the charging start time.

The charge controller may be configured to selectively connect the electronic device to an energy supply in accordance with the charging parameter. The charge controller may be configured to operate a switch between an energy supply and the electronic device such that charging begins at the charging start time.

The charge controller may be configured to selectively enable an associated energy supply in accordance with the charging parameter The charge controller may be configured to receive the charging end time from alarm application software. The charge controller may be configured to receive a target charge level and / or the charging end time from a user interface.

The charge controller may be configured to initiate a supplemental charging event in accordance with the charging parameter and a charge level profile. The charge controller may be configured to set a duration of the supplemental charging event such that a charge level of the electronic device is expected to be at a predetermined level at a charging start time.

The charge controller may be configured to cause an energy supply to charge the electronic device in response to a charge level of the electronic device falling below a low-charge threshold value.

The charge controller may be configured to cause an energy supply to stop charging the electronic device in response to a charge level of the electronic device exceeding a high-charge threshold value.

The charge controller may be associated with the electronic device, or with the energy supply.

There is also disclosed a charging system comprising: an energy supply; and a charge controller configured to: determine a charging parameter for an electronic device based on a target charge level at a charging end time; and cause the energy supply to provide energy to the electronic device in accordance with the determined charging parameter.

There is also disclosed a method comprising: determining a charging parameter for an electronic device based on a charging end time.

The method may comprise: identifying a period of charging time associated with the difference between a target charge level at the charging end time and a predicted charge level for the start of a charging event; and subtracting the period of charging time from the charging end time in order to determine the charging start time.

The method may comprise: i) identifying a current charge level of the electronic device; ii) setting a predicted charge level for the start of the charging event as the current charge level of the electronic device; iii) determining the charging start time based on a charging profile of the electronic device using the predicted charge level for the start of the charging event, such that the electronic device will have a target charge level at the charging end time; iv) setting the predicted charge level for the start of the charging event by using the charge level profile to determine the expected charge level at the charging start time that was determined at step iii); and v) returning to step iii) at least once in order to determine a revised value for the charging start time based on the modified value for the predicted charge level for the start of the charging event.

There is also disclosed a charge controller configured to automatically cause an energy supply to charge an electronic device in response to a charge level of the electronic device falling below a low-charge threshold value.

Such a charge controller can advantageously reduce the likelihood of a charge level of a battery associated with the electronic device falling to an unacceptably low level, such as becoming sufficiently discharged that the electronic device shuts down.

The charge controller may be configured to connect the electronic device to the energy supply in order to charge the electronic device. The charge controller may be configured to operate a switch between the energy supply and the electronic device in order to charge the electronic device. The charge controller may be configured to enable the energy supply in order to charge the electronic device.

The energy supply may be a fuel cell system. The controller may be configured to initiate a supply of fuel to the fuel cell system in order to charge the electronic device.

The charge controller may be configured to automatically cause the energy supply to stop charging the electronic device in response to the charge level of the electronic device exceeding a high-charge threshold value. The charge controller may be configured to disconnect the electronic device from the energy supply in order to stop charging the electronic device. The charge controller may be configured to disable the energy supply to in order to stop charging the electronic device. The controller may be configured to interrupt a supply of fuel to the fuel cell system in order to stop charging the electronic device.

There is also disclosed a method comprising: automatically causing an energy supply to charge an electronic device in response to a charge level of the electronic device falling below a low-charge threshold value.

The method may further comprise: automatically causing the energy supply to stop charging the electronic device in response to the charge level of the electronic device exceeding a high-charge threshold value.

There may be provided a computer program, which when run on a computer, causes the computer to configure any apparatus, including a controller, system, or device disclosed herein or perform any method disclosed herein. The computer program may be a software implementation, and the computer may be considered as any appropriate hardware, including a digital signal processor, a microcontroller, and an implementation in read only memory (ROM), erasable programmable read only memory (EPROM) or electronically erasable programmable read only memory (EEPROM), as non-limiting examples. The software may be an assembly program.

The computer program may be provided on a computer readable medium, which may be a physical computer readable medium such as a disc or a memory device, or may be embodied as a transient signal. Such a transient signal may be a network download, including an internet download.

Embodiments of the present invention will now be described by way of example and with reference to the accompanying drawings in which: Figure 1 shows a charging system that includes an energy supply and an electronic device; Figure 2 shows an example of a charging profile for an electronic device; Figure 3 shows an example of a charge level profile for an electronic device; Figure 4 shows an example of an energy usage profile for an electronic device; and Figure 5 shows another example of a charge level profile for an electronic device.

Figure 1 shows a charging system 100 that includes an energy supply 104 and an electronic device 102. The energy supply 104 may be a mains electricity supply, or any other type of energy supply. For example, the energy supply 104 may be a fuel cell system such as a portable hydrogen fuel cell system that includes a removable hydrogen fuel container. The electronic device 102 may be a portable computing device such as a mobile telephone, a smart phone, a tablet computer or any other portable communications device.

The electronic device 102 has a battery, or any other energy storage device, that can be charged by the energy supply 104.

Figure 1 also shows a charge controller 106 associated with the electronic device 102. The charge controller 106 can be implemented as hardware or software, for example it can be implemented as an app on the electronic device 102. It will however be appreciated that the functionality of the charge controller 106 can be associated with the energy supply 104 (as shown with reference number 108 in figure 1), the functionality can be distributed between the electronic device 102 and the energy supply 104, or it can be provided by a third party device (not shown) that is in electronic communication with the electronic device 102 and / or the energy supply 104.

In this example, the charge controller 106 can determine a charging parameter for the electronic device 102 based on a charging end time, and optionally a target charge level for the charging end time. As will be discussed in more detail below, in one implementation this can enable a user to postpone the start of a charging event such that at a specific charging end time (for example at 7:00 when the user intends to wake up in the morning), the electronic device 102 is charged to a target charge level (for example 90%). This implementation may be referred to as dynamically-delayed charging. This can enable more efficient charging because the electronic device 102 may not need to be in a trickle charge mode of operation for a long time after the electronic device 102 has been fully charged, before the user wakes up in the morning.

The charge controller 106 can receive the charging end time from a user interface. For example, an app associated the electronic device 102 can enable a user to enter this information. Alternatively or additionally, the charge controller 106 can receive the charging end time from alarm application software. In such an example the charging end time can be automatically set as the time at which an alarm is scheduled, or any other event is scheduled. Further still, a user interface associated with the alarm application software can simply provide a user with a selectable option for the electronic device 102 to be fully charged (or charged to any specific level) when the alarm time is reached. In this way, at least part of the charge controller functionality can be provided by the alarm application software, or by any other device native software.

The charge controller 106 can determine the charging parameter for the electronic device 102 based on the charging end time in a number of ways, as described below. In the examples that follow, the charging parameter is a "charging start time".

In one implementation, the charge controller 106 can utilise data representative of a fixed charging period that corresponds to a period of time that is required to fully charge the electronic device 102. In such an implementation the charge controller 106 can subtract the fixed charging period from the received charging end time in order to determine the charging start time. Determining the charging start time in this way can be computationally easy and can ensure that the electronic device 102 is full charged at the charging end time. Also, the charge level of the electronic device 102 can be allowed to fall to zero, or go into a power-saving mode, before the charging event is started. If the electronic device 102 has some charge at the charging start time, then the electronic device 102 may be fully charged before the charging end time. However, in some applications, any trickle charging that occurs after the electronic device 102 is full charged, and before the charging end time is reached, can be considered acceptably low.

Figure 2 shows an example of a charging profile 200 for an electronic device. The vertical axis represents voltage. The horizontal axis represent time. The voltage on the vertical axis can also be labelled as a charge level between 0% and 100%. The charge controller can determine the charging start time for the electronic device based on the charging profile 200.

In one implementation, the charge controller can identify the target charge level 210 on the charging profile 200. Then, using a predicted charge level for the start of the charging event 212 (as will be discussed below), the charge controller can identify a period of charging time 214 associated with the difference between the target charge level 210 and the predicted charge level for the start of the charging event 212. This period of charging time 214 can then be subtracted from the charging end time in order to determine the charging start time. In this way, the charge controller can determine the charging start time based on the charging profile 200 such that the electronic device has, at least approximately, the target charge level 210 at the charging end time.

In one example, the predicted charge level for the start of the charging event 212 can be set as the charge level of the electronic device at a time that a user provides an input indicative of a desire to use dynamically-delayed charging, at which time the charging start time can be calculated. This example can be used if the expected energy usage after the charging start time has been determined, and before the charging event begins, can be considered as sufficiently small to not matter. Optionally, the charge controller can cause the electronic device to shut itself down when the charging start time has been set, such that the charge level for the start of the charging event will correspond to the predicted charge level for the start of the charging event.

In a further example, the charge controller can determine a charge-delay period between (i) the instant in time that the start of the charging event is calculated, and (ii) the calculated start of the charging event 212. The charge controller can then compare the charge-delay period with one or more delay thresholds and, if the charge-delay period is greater than the delay threshold, then the charge controller can schedule a recalculation of the start of the charging event 212 partway through the charge-delay period. In this way, the start of the charging event 212 can be updated before the charging event starts such that it can be more accurately set, if there is a sufficiently long delay before the charging event is due to start.

It will be appreciated that the processing described above with reference to the charging profile 200 can be performed by applying a mathematical function that represents the charging profile 200, or can be performed by using a database or look up table that stores data points associated with the charging profile 200.

In the examples described with reference to figure 2, the charge controller may not require a charge level profile or an energy usage profile to determine the charging start time.

Figure 3 shows an example of a charge level profile 300 for an electronic device. The vertical axis represents the charge level of a battery or other energy storage device associated with the electronic device. The horizontal axis represent time, The charge level profile 300 can comprise historical, measured, charge level data (as shown with a solid line in figure 3), and can also contain predicted, future, charge level data (as shown with a dashed line in figure 3). The predicted, future, charge level data can be determined based on the immediately preceding charge level data, and / or can be determined based on energy usage data from the same time of day on previous days (an energy usage profile is described below with reference to figure 4). Alternatively, the predicted, future, charge level data can be based on predetermined energy usage information. Such predetermined energy usage information can be based on an expected energy usage when the electronic device is in a low/zero-usage mode of operation.

In one implementation, the charge controller can determine the charging start time based on the charge level profile 300. For example, when a user provides an indication that they wish to use dynamically-delayed charging, the charge controller can: i) identify a current charge level of the electronic device, for example using the charge level profile 300; ii) set a predicted charge level for the start of the charging event as the current charge level of the electronic device; iii) determine the charging start time based on a charging profile of the electronic device (for example in the way described above with reference to figure 2) using the predicted charge level for the start of the charging event, such that the electronic device will have the target charge level at the charging end time; iv) modify the predicted charge level for the start of the charging event. This can be achieved by using the charge level profile 300 to determine the expected charge level at the charging start time that was determined at step iii); and v) return to step iii) in order to determine a revised value for the charging start time based on the modified value for the predicted charge level for the start of the charging event.

It will be appreciated that steps Hi) and iv) can be repeated once, or a plurality of times, in accordance with step v). That is, the process may end after step iv) has been performed a predetermined number of times. Alternatively or additionally, the charge controller may monitor how the charging start time is changing with each iteration of the process, and cause the process to end once the difference between successively determined values for the charging start time is less than a threshold value.

Figure 4 shows an example of an energy usage profile 400 for an electronic device. The vertical axis represents energy usage of the electronic device. The horizontal axis represents time. The energy usage profile 400 can comprise historical, measured, energy usage data (as shown with a solid line in figure 4), and can also contain predicted, future, energy usage data (as shown with a dashed line in figure 4). The predicted, future, energy usage data can be determined in the same was as described with reference to figure 3. It will be appreciated that in some examples the energy usage profile 400 can be considered as representing the same information as the charge level profile of figure 3.

In one implementation, the charge controller can determine the charging start time based on the energy usage profile 400. For example, the charge controller can: i) identify a current charge level of the electronic device; ii) set a predicted charge level for the start of the charging event as the current charge level of the electronic device; iii) determine the charging start time based on a charging profile of the electronic device (for example in the way described with reference to figure 2) using the predicted charge level for the start of the charging event, such that the electronic device will have the target charge level at the charging end time; iv) modify the predicted charge level for the start of the charging event in accordance with the energy usage profile 400, in order to determine the expected charge level at the charging start time that was determined at step iii). This can be achieved by determining the amount of charge that is expected be used by the electronic device in the time window between a) the current time, and b) the time determined as the charging start time at step iii); and v) return to step iii) in order to determine a revised value for the charging start time based on the modified value for the predicted charge level for the start of the charging event.

As with the description of figure 3, steps iii) and iv) can be repeated any number of times.

Returning to figure 1, once the determined charging start time is reached, the charge controller 106 should initiate the charging event that is intended to result in the electronic device 102 being charged to a target charge level at the charging end time. The initiation of the charging event can be achieved in a number of ways.

In one example, the charge controller 106 can selectively enable the energy supply 104 in accordance with the charging start time. In one implementation, the charge controller 106 can transmit a start-up signal to the energy supply 104 in accordance with the charging start time. The start-up signal can be transmitted at the charging start time with an instruction for the energy supply 104 to immediately start supplying energy to the electronic device 102. If the energy supply 104 is a fuel cell system, then upon receipt of the start-up signal the fuel cell system can initiate a supply of fuel to the fuel cell system.

Optionally, the charge controller 106 can transmit the start-up signal to the energy supply 104 in advance of the charging start time. The start-up signal can include the start-up time, or a charge-delay period to be waited before starting to charge. The energy supply io 104 can then store data representative of the charging start time or charge-delay period such that it can itself initiate the charging event at a future moment in time. In such an example, the charge level of the electronic device 102 may be permitted to drop to zero because the electronic device 102 is no longer required to be operational at the charging start time to initiate the charging event.

In some examples, the charge controller 106 can selectively connect the electronic device 102 to the energy supply 104 in accordance with the charging start time. In one implementation, a switch (not shown) can be located between the energy supply 104 and the electronic device 102. Energy can be allowed to flow from the energy supply 104 to the electronic device 102 when the switch is closed, whereas energy is prevented from flowing from the energy supply 104 to the electronic device 102 when the switch is open. The charge controller 106 can operate the switch such that charging begins at the charging start time.

In some implementations, the charge controller 106 can optionally disable the energy supply 104 or disconnect the electronic device 102. Such disablement or disconnection may be automatically performed in accordance with the charging end time. Disabling the energy supply 104 may involve stopping a supply of fuel to fuel cell system, and / or in some examples electronically disabling the energy supply 104. Disconnecting the electronic device 102 may involve opening an electronic switch between the energy supply 104, and / or in some examples physically disconnecting the electronic device 102.

It will be appreciated from the above examples that the charge controller 106 may periodically or selectively recalculate the charging parameter. Such selective recalculation may be based on a delay period before which the charging event is scheduled to start, and charge level, as non-limiting examples.

Figure 5 shows another example of a charge level profile 500 for an electronic device. In this example, the charge controller can perform additional processing on the data represented by the charge level profile 500.

On the time axis, figure 5 shows the current moment in time 524 and a determined value for the charging start time 522. The charge level profile 500 comprises historical, measured, charge level data (as shown with a solid line in figure 5), and also contains predicted, future, charge level data (as shown with a dashed line in figure 5). A low-charge threshold level 520 for the charge level is also shown in figure 5. In some examples the low-charge threshold level 520 may be zero.

Figure 5 shows that as time progresses, the charge level profile 500 is expected to reach the low-charge threshold level 520 at a time shown with reference 526, which is before the charging start time 522. In this example, in order to prevent the electronic device from becoming completely discharged, the charge controller can initiate a supplemental / boost charging event before the charging event that is intended to result in the electronic device having the target charge level at the charging end time.

In one implementation, after the charging start time 522 has been calculated, the charge controller processes the charge level profile 500 and the charging start time 522 in order to determine if the low-charge threshold level 520 is expected to be reached before the charging start time 522. If it is, as shown in figure 5, then the charge controller can schedule the supplemental charging event to start at the time that the electronic device's charge level is expected to reach the low-charge threshold level 520. This is shown in figure 5 as the increase in charge level profile 500 at the instant in time 526 that the charge level profile reaches the low-charge threshold level 520, In another example, the charge controller can initiate the supplemental charging event earlier, optionally shortly after the need for a supplemental charging event has been identified, such that the charge level profile 500 should not reach the low-charge threshold level 520.

The duration of the supplemental charging event can be determined by the charge controller such that the charge level profile is expected to be at a predetermined level at the charging start time 522. In the example shown in figure 5, the predetermined level is the low-charge threshold level 520. In this way, efficient charging can be provided because the supplemental charging event can be kept as short as possible. without requiring more than one supplemental charging event.

Alternatively, the duration of the supplemental charging event may be a predetermined fixed value. Optionally, the charging start time 522 can be recalculated after the supplemental charging event has been completed.

The charge level profile 500 of figure 5 will now be used to describe functionality of a charge controller that can be provided independently of the functionality described above in relation to use of the charging start time, or can be used in combination with the functionality related to the charging start time.

In some examples the charge controller can automatically connect the electronic device to the energy supply for charging in response to the charge level 500 of the electronic device falling below the low-charge threshold level 520. The charge controller can periodically monitor the charge level profile 500 and if the charge level profile 500 reaches the low-charge threshold level 520, then a supplemental charging event can be initiated. In examples where the charge controller is associated with the energy supply, the energy supply can monitor the state of charge of the (external) electronic device and determine that charging is needed and then start the charge.

The supplemental charging event can have a fixed duration, or a dynamically determined duration, as discussed above. The fixed duration may be a period of time that is expected to fully charge the electronic device. This can reduce or minimise the number of supplemental charging events.

The charge controller can also cause the energy supply to stop charging the electronic device in response to the charge level of the electronic device exceeding a high-charge threshold value (not shown in figure 5), for example by automatically disconnecting the electronic device from the energy supply. The high-charge threshold value may correspond to the electronic device being fully charged.

Use of this automatic connection and disconnection functionality can enable an electronic device, such as an emergency radio / beacon, to be kept fully charged for years by a hydrogen fuel cell system that has access to only a limited volume of hydrogen. This can be better than battery back-up solutions that suffer from self-discharge of the batteries. In such an example, when the electronic device's battery is low (as defined by the electronic device) the radio I beacon can request an energy top-up from the hydrogen fuel cell system using the charge controller.

Another use of the automatic connection and disconnection functionality relates to WiFi hot-spot electronic devices that run off internal batteries. The charge controller can receive battery level information and determine when to start-charging the hot-spot battery.

Examples disclosed herein can relate to starting a fuel cell charger in a controlled manner using an in-built switch or an external device. In particular, a particular time at which the device automatically starts up can be set. Examples relate to a fuel cell charger (a) being woken up by a communication from external device when charging is needed (b) receiving a communication from an external device informing the charger of a particular time the charger is to start charging, after which the device shuts-down/sleeps waiting for the charge to start (c) monitoring the state of charge of an external device by the charger and determining that charging is needed and then starting the charge.

Claims

Claims 1. A charge controller configured to determine a charging parameter for an electronic device based on a charging end time.
2. The charge controller of claim 1, wherein the charging parameter comprises a charging start time.
3. The charge controller of claim 1, wherein the charging event parameter comprises lo a charging start time, and wherein the charge controller is configured to determine the charging start time based on a charging profile such that the electronic device has a target charge level at the charging end time.
4. The charge controller of claim 1, configured to determine a charging parameter for is an electronic device based on a target charge level at the charging end time.
5. The charge controller of claim 1, wherein the charge controller is configured to determine the charging event parameter for the electronic device based on a charging profile for the electronic device.
6. The charge controller of claim 1, wherein the charge controller is configured to determine the charging parameter based on an energy usage profile.
7. The charge controller of claim 1, wherein the charge controller is configured to periodically recalculate the charging parameter.
8. The charge controller of claim 1, wherein the charge controller is configured to selectively, based on a charge level of the electronic device, recalculate the charging parameter.
9. The charge controller of claim 1, wherein the charge controller is configured to selectively, based on the determined charging parameter, recalculate the charging parameter.
10. The charge controller of claim 1, wherein the charge controller is configured to transmit a start-up signal to an energy supply in accordance with the charging start time.
11. The charge controller of claim 10, wherein the energy supply comprises a fuel cell system.
12. The charge controller of claim 10, wherein the controller is configured to transmit the start-up signal to the energy supply at the charging start time.
13. The charge controller of claim 10, wherein the controller is configured to transmit the start-up signal to the energy supply in advance of the charging start time, such that the energy supply will start providing energy at the charging start time.
14. The charge controller of claim 1, wherein the charge controller is configured to selectively connect the electronic device to an energy supply in accordance with the charging parameter.
15. The charge controller of claim 1, wherein the charge controller is configured to operate a switch between an energy supply and the electronic device such that charging begins at the charging start time.
16. The charge controller of claim 1, wherein the charge controller is configured to selectively enable an associated energy supply in accordance with the charging parameter
17. The charge controller of claim 1, wherein the charge controller is configured to receive the charging end time from alarm application software.
18. The charge controller of claim 1, wherein the charge controller is configured to receive a target charge level and / or the charging end time from a user interface.
19. The charge controller of claim 1, wherein the charge controller is configured to initiate a supplemental charging event in accordance with the charging parameter and a charge level profile.
20. The charge controller of claim 19, wherein the charge controller is configured to set a duration of the supplemental charging event such that a charge level of the electronic device is expected to be at a predetermined level at a charging start time.
21. The charge controller of claim 1, wherein the charge controller is configured to cause an energy supply to charge the electronic device in response to a charge level of the electronic device falling below a low-charge threshold value.
22. The charge controller of claim 1, wherein the charge controller is configured to cause an energy supply to stop charging the electronic device in response to a charge level of the electronic device exceeding a high-charge threshold value.
23. A charging system comprising: an energy supply; and a charge controller configured to: determine a charging parameter for an electronic device based on a target charge level at a charging end time; and cause the energy supply to provide energy to the electronic device in accordance with the determined charging parameter.
24. A method comprising: determining a charging parameter for an electronic device based on a charging end time.
25. The method of claim 24, wherein the charging parameter is a charging start time, and wherein the method comprises: identifying a period of charging time associated with the difference between a target charge level at the charging end time and a predicted charge level for the start of a charging event; and subtracting the period of charging time from the charging end time in order to determine the charging start time.
26. The method of claim 24, wherein the charging parameter is a charging start time, 30 and wherein the method comprises: i) identifying a current charge level of the electronic device; ii) setting a predicted charge level for the start of the charging event as the current charge level of the electronic device; iii) determining the charging start time based on a charging profile of the electronic device using the predicted charge level for the start of the charging event, such that the electronic device will have a target charge level at the charging end time; iv) setting the predicted charge level for the start of the charging event by using the charge level profile to determine the expected charge level at the charging start time that was determined at step iii); and v) returning to step iii) at least once in order to determine a revised value for the charging start time based on the modified value for the predicted charge level for the start of the charging event.
27. A computer program configured to perform the method of claim 26.
28. A charge controller configured to automatically cause an energy supply to charge an electronic device in response to a charge level of the electronic device falling below a low-charge threshold value.
29. The charge controller of claim 28, wherein the charge controller is configured to connect the electronic device to the energy supply in order to charge the electronic device.
30. The charge controller of claim 28, wherein the charge controller is configured to operate a switch between the energy supply and the electronic device in order to charge the electronic device.
31. The charge controller of claim 28, wherein the charge controller is configured to enable the energy supply in order to charge the electronic device.
32. The charge controller of claim 28, wherein the energy supply is a fuel cell system, and wherein the controller is configured to initiate a supply of fuel to the fuel cell system in order to charge the electronic device.
33. The charge controller of claim 28, wherein the charge controller is configured to automatically cause the energy supply to stop charging the electronic device in response to the charge level of the electronic device exceeding a high-charge threshold value.
34. The charge controller of claim 33, wherein the charge controller is configured to disconnect the electronic device from the energy supply in order to stop charging the electronic device.
35. The charge controller of claim 33, wherein the charge controller is configured to disable the energy supply in order to stop charging the electronic device.
36. The charge controller of claim 33, wherein the energy supply is a fuel cell system, and wherein the controller is configured to interrupt a supply of fuel to the fuel cell system in order to stop charging the electronic device.
37. A method comprising: automatically causing an energy supply to charge an electronic device in response to a charge level of the electronic device falling below a low-charge threshold value.o
38. The method of claim 37, wherein the method further comprises: automatically causing the energy supply to stop charging the electronic device in response to the charge level of the electronic device exceeding a high-charge threshold value.
39. A charge controller substantially as disclosed herein, and as illustrated in the accompanying drawings.
40. A charging system substantially as disclosed herein, and as illustrated in the accompanying drawings.
41. A method substantially as disclosed herein, and as illustrated in the accompanying drawings.