Field of the Invention
The present invention relates to a portable battery pack, such as a portable battery pack for use in rural communities without access to mains electricity. The present invention also relates to an activation station for a portable battery pack, an authorisation server and a system.
Background of the Invention
In some parts of the world, such as rural Africa, individual households and whole communities have no access to mains electricity. The remote nature of the locations involved means that installing mains electricity is not economically viable.
Small scale renewable energy schemes, such as solar panels or wind turbines, can provide electricity to these households and communities. However, the cost of installing and maintaining solar panels or wind turbines can prove prohibitively expensive. Also, renewable energy tends to be unable to supply electricity continuously, for example, because there is not always sufficient wind to operate a wind turbine.
Given the lack of mains electricity, people in these communities frequently rely on paraffin lamps for lighting. Paraffin lamps give off toxic fumes, are a fire hazard, and produce little light. Battery operated lights are far superior but few people can afford to purchase the batteries needed to run them, and rechargeable batteries still need a source of electricity for charging.
Many people in these communities have mobile phones and smartphones, but a lack of mains electricity means that charging these phones can be challenging, restricting the amount people can use their phone.
Some entrepreneurs operate outlets providing battery rental, where a charged battery may be rented for a period of time and returned when empty. However, many batteries are stolen which has led to a lack of desire to invest in battery rental businesses. As a result, there are too few outlets, forcing many people to walk significant distances to rent a battery. A lack of safety features on the available rental batteries and charging infrastructure mean that there is a risk that the battery will be faulty, not delivering a full charge, and may even risk overheating and catching fire.

It would, therefore, be desirable to find a portable battery pack, and associated charging infrastructure, which overcomes these problems and makes electrical power more available to households and communities in areas without access to mains electricity.

Summary of the Invention

According to a first aspect of the invention, there is provided a portable battery pack. The portable battery pack has an input, one or more cells configured to store electrical energy, and a processor. The processor is configured to control at least one of: charging of the one or more cells based on a charging authorisation signal received at the input; and discharging of the one or more cells based on a discharging authorisation signal received at the input.

The fact that the portable battery pack has a processor which controls at least one of charging of the one or more cells based on a charging authorisation signal and discharging of the one or more cells based on a discharging authorisation signal means that charging and/or discharging of the portable battery pack is only allowed when pre-authorised (for example, by an authorisation server) which allows the portable battery pack to be remotely controlled.

The remote control of charging and/or discharging means that the portable battery pack is more likely to be charged by authorised equipment, because unauthorised equipment is unlikely to be able to provide the necessary signal to authorise charging and/or discharging.

Encouraging charging by authorised equipment improves safety, as charging the portable battery pack on an unauthorised charger leads to an increased risk of overheating of the portable battery pack which could even lead to fire.

Discharging may be disabled, for example, if the battery is old or faulty, again improving safety and reducing the incidence of poor performance associated with old or faulty portable battery packs.

The remote control of charging and/or discharging also means that portable battery packs are less prone to theft (because they cannot be charged by unauthorised equipment, there is less incentive to steal the battery packs). As the portable battery packs are less prone to theft, this will reduce the cost of the portable battery packs and provide a guaranteed rental income which will encourage investment in portable battery pack technology and associated infrastructure, making portable battery pack technology more available to people in rural areas, such as rural Africa, who will then benefit by having better access to cheap and reliable electricity in their homes. A source of cheap and reliable electricity will offer improvements to their lives, such as access to mobile communications and lighting which will allow, them, for example, to study and become better educated.

The processor may be configured to enable charging of the one or more cells when the charging authorisation signal indicates that charging is authorised.

The processor may be configured to disable charging of the one or more cells when the charging authorisation signal indicates that charging is not authorised.

The processor may be configured to enable discharging of the one or more cells when the discharging authorisation signal indicates that discharging is authorised.

The processor may be configured to disable discharging of the one or more cells when the discharging authorisation signal indicates that discharging is not authorised.

The portable battery pack may comprise one or more switches, such as one or more relays or transistors.

The portable battery pack may comprise a discharging switch. The discharging switch may be closed by the processor in response to the discharging authorisation signal indicating that discharging is authorised, which allows the one or more cells to be discharged. The discharging switch may be opened by the processor in response to the discharging authorisation signal indicating that discharging is not authorised, which prevents the one or more cells being discharged.

The portable battery pack may comprise a charging switch. The charging switch may be closed by the processor in response to the charging authorisation signal indicating that charging is authorised, which allows the one or more cells to be charged. The charging switch may be opened by the processor in response to the charging authorisation signal indicating that charging is not authorised, which prevents the one or more cells being charged.

The processor may be configured to disable discharging of the one or more cells after a period of time has elapsed. The fact that the processor is configured to disable discharging of the one or more cells after a period of time has elapsed means that discharging of the portable battery pack can be pre-authorised for a limited period of time. This may help to reduce theft, for example, because the portable battery pack must be reconnected to an activation station before further discharging is authorised.

The processor may receive a signal from the input indicating the period of time. The period of time may be one of: a period of time since discharging of the one or more cells was authorised; a period of time since discharging of the one or more cells first began following the last time discharging of the one or more cells was authorised; or a sum of the discharge time since the last time discharging of the one or more cells was authorised.

The processor may be further configured to send identifying information, for example, to an external device such as an activation station. The processor may have an output to which the identifying information is sent. An advantage of the processor being further configured to send identifying information to the activation station is that the activation station can identify the portable battery pack, for example, to determine that the portable battery pack is authorised for charging and/or discharging, or that the portable battery pack has not been marked for retirement or marked as faulty.

The portable battery pack may have a connection to allow the portable battery pack to be connected to an external charge controller. The cells may be configured to be charged using the external charge controller. An advantage of the cells being configured to be charged by an external charge controller (that is, a charge controller which is not part of the portable battery pack) is that the portable battery pack does not need its own charge controller, eliminating the additional weight and bulk of a charge controller from the portable battery pack and reducing the cost of the portable battery pack. Also, by making the charge controller external to the portable battery pack, the charger controller may be larger, more efficient and better cooled, and therefore may be able to charge the portable battery pack more quickly and efficiently.

The processor may be further configured to send a charging specification to the external charge controller. An advantage of the processor being further configured to send a charging specification to the external charge controller is that the portable battery pack can indicate the preferred charging conditions of the portable battery pack, thereby ensuring that optimum charging of the portable battery pack is achieved, based on the type of cells in the portable battery pack, thereby improving the lifetime of the cells and reducing the risk of failure, damage, overheating or fire.

The portable battery may further comprise a memory configured to store a log file.

The log file may contain historical usage information of the portable battery pack. For example, the log file may contain: the number of times the portable battery pack has been charged and/or discharged; the current draw profile for each occasion the portable battery pack has been discharged; the total length of discharge since the last charge; the charging conditions for each occasion the portable battery pack has been charged (such as the voltage and/or current supplied during charging); and any errors or faults that have occurred.

The log file may be used to determine when the portable battery pack should be retired because it is old or faulty. For example, the log file may indicate that the one or more cells in the portable battery pack are not performing adequately; or may record that the one or more cells were exhausted before the period of time expired.

The log file may be sent to an activation station when the portable battery pack is connected to the activation station.

The portable battery pack may receive depth of discharge information, for example, from the input. The processor may disable discharging based on the depth of discharge information. This allows depth of discharge to be dynamically controlled by the activation station, to manipulate charging time while seeking to maximise the life of the battery. Over-discharging the cells may be avoided where unnecessary (for example, when there is sufficient time to fully charge the cells). However, if there is insufficient time to fully charge the cells, the signal may be configured to indicate that the end of discharge voltage may be dropped so that the cells appear to a user to have been given a full charge.

The input may be connected to an activation station. The input may be connected periodically to the activation station. The input may be connected to the activation station by a wired or wireless connection. The processor may be configured to send when the portable battery pack is connected to an activation station.

The processor may be configured to communicate over a secure communication link. The processor may be configured to communicate with the activation server over a secure communication link. Communicating over a secure communications link makes it more difficult for a third party to intercept the signal and determine a signal which could be used to authorise charging and/or discharging of the portable battery pack, which helps to prevent unauthorised equipment from charging the portable battery pack or prevents unauthorised equipment from authorising the portable battery pack to be discharged.

The processor may initiate the secure communication link using challenge-response authentication. The processor may provide a challenge to an activation station connected to the portable battery pack. The activation station may provide a response in reply to the challenge. The processor may only initiate secure communications with the activation station if a correct response is received. This means that the activation station will only be able to enable and/or disable charging and/or discharging if the activation station is able to provide the correct response. The use of challenge-response authentication therefore helps to prevent unauthorised equipment from charging the portable battery pack or prevents unauthorised equipment from authorising the portable battery pack to be discharged

The secure communication link may be encrypted.

The secure communication link may comprise a tunnel to an authorisation server.

An authorisation server may provide authorisation information to the activation station.

The secure communications link may use communications hardware in the activation station (such as a modem) so that the portable battery pack does not need to include the extra cost and weight of a modem, and so that only one modem is needed in an activation station which can be shared with all the portable battery packs that are charged at that activation station, significantly reducing the cost of the portable battery packs.

The portable battery pack may further comprise an electrical output configured to provide electrical energy to a device connected to the electrical output. The output may be a USB socket.

The output may be configured to provide electrical energy to the device connected to the electrical output only when discharging is authorised.

A portable battery pack is designed to be carried or moved easily by a user, for example, to allow the user to take the portable battery pack home to provide electricity in their home, or to allow the user to carry the portable battery pack with them to provide a mobile source of electricity.

According to a second aspect of the invention, there is provided an activation station for a portable battery pack. The activation station comprises an output and a processor. The processor is configured to send, to the output, at least one of: a charging authorisation signal that indicates to the portable battery pack whether charging of the one of more cells is authorised; and a discharging authorisation signal that indicates to the portable battery pack whether discharging of the one or more cells is authorised.

The fact that the activation station sends to the output (which may be connected to the portable battery pack) at least one of a charging authorisation signal that indicates to the portable battery pack whether charging of the one of more cells is authorised and a discharging authorisation signal that indicates to the portable battery pack whether discharging of the one or more cells is authorised means that charging and/or discharging of the portable battery pack is only allowed when pre-authorised (for example, by an authorisation server) which allows the portable battery pack to be remotely controlled.

The remote control of charging and/or discharging means that the portable battery pack is more likely to be charged by authorised equipment, because unauthorised equipment is unlikely to be able to provide the necessary signal to authorise charging and/or discharging.

Encouraging charging by authorised equipment improves safety, as charging the portable battery pack on an unauthorised charger leads to an increased risk of overheating of the portable battery pack which could even lead to fire.

Discharging may be disabled, for example, if the battery is old or faulty, again improving safety and reducing the incidence of poor performance associated with old or faulty portable battery packs.

The remote control of charging and/or discharging also means that portable battery packs are less prone to theft (because they cannot be charged by unauthorised equipment, there is less incentive to steal the battery packs). As the battery packs are less prone to theft, this will reduce the cost of the battery packs and provide a guaranteed rental income which will encourage investment in portable battery pack technology and associated infrastructure, making portable battery pack technology more available to people in rural areas, such as rural Africa, who will then benefit by having better access to cheap and reliable electricity in their homes. A source of cheap and reliable electricity will offer improvements to their lives, such as access to mobile communications and lighting which will allow, for example, them to study and become better educated.

The processor may be configured to send, to the output, a charging authorisation signal that indicates that charging of the one or more cells is authorised.

The processor may be configured to send, to the output, a charging authorisation signal that indicates that charging of the one or more cells is not authorised.

The processor may be configured to send, to the output, a discharging authorisation signal that indicates that discharging of the one or more cells is authorised.

The processor may be configured to send, to the output, a discharging authorisation signal that indicates that discharging of the one or more cells is not authorised.

The processor may be configured to send a signal to the output indicating that charging of the one or more cells is not authorised when a desired charge level of the one or more cells is obtained. This prevents further charging of the one or more cells of the portable battery pack once the one or more cells have reached a desired charge level (such as fully charged, or an authorised charge level) so that the portable battery pack must be reconnected to an activation station to be recharged again which helps to prevent the portable battery pack being recharged on unauthorised equipment and reduces the incentive to steal a portable battery pack.

The processor may be configured to send a signal to the output indicating that discharging of the one or more cells is authorised when a desired charge level of the one or more cells is obtained.

The activation station may communicate over a secure communication link. Communicating over a secure communication link makes it more difficult for a third party to intercept the signal and determine a signal that could be used to authorise charging and/or discharging of the portable battery pack, which helps to prevent unauthorised equipment from charging the portable battery pack or prevents unauthorised equipment from authorising the portable battery pack to be discharged.

The secure communication link may use challenge-response authentication. The processor may receive a challenge from a portable battery pack connected to the activation station. The processor may provide a response to the challenge. Communication between the activation station and portable battery pack will only be initiated if the activation station provides a correct response. This means that the activation station will only be able to enable and/or disable charging and/or discharging if the activation station is able to provide the correct response. The use of challenge-response authentication therefore helps to prevent unauthorised equipment from charging the portable battery pack or prevents unauthorised equipment from authorising the portable battery pack to be discharged

secure communication link may be encrypted.

The processor may be configured to generate the charging authorisation signal based on authorisation information obtained from a server, such as an authorisation server.

The processor may be configured to generate the discharging authorisation signal based on authorisation information obtained from a server, such as an authorisation server.

The authorisation information may indicate whether charging and/or discharging of the one or more cells is authorised. The authorisation server may hold information about a plurality of portable battery packs, indicating whether each portable battery pack of the plurality of battery packs is authorised for charging and/or discharging. The authorisation server may also hold information about portable battery packs of the plurality of battery packs that are faulty or retired, and may indicated that they will never again be authorised for charging and/or discharging.

The activation station may further comprise a modem configured to obtain the authorisation information from the server. By providing a modem in the activation station, the portable battery pack need not include the extra cost and weight of a modem, so that only one modem is needed in an activation station which may charge many portable battery pack, significantly reducing the cost of the portable battery packs.

The secure communications link may comprise a tunnel between the portable battery pack and an authorisation server using the modem.

The activation station may send identifying information, received from a portable battery pack, to the authorisation server.

The modem may relay the identifying information received from the portable battery pack to the authorisation server over a secure communications tunnel using the modem. The authorisation server may relay the signal, indicating whether charging and/or discharging of the one or more cells is authorised, to the portable battery pack over a secure communications tunnel using the modem.

The processor may send a signal which indicates a period of time after which discharging of the one or more cells is to be disabled. This means that discharging of the portable battery pack can be pre-authorised for a limited period of time. This may help to reduce theft because the portable battery pack must be reconnected to an activation station before further discharging is authorised.

The period of time may be one of: a period of time since discharging of the one or more cells was authorised; a period of time since discharging of the one or more cells first began following the last time discharging of the one or more cells was authorised; or a sum of the discharge time since the last time discharging of the one or more cells was authorised.

The activation station may have an input configured to receive identifying information from the portable battery pack. An advantage of this is that the activation station can identify the portable battery pack, for example, to determine whether the portable battery pack is authorised for charging and/or discharging, or that the portable battery pack has not been marked for retirement or marked as faulty.

The activation station processor may send the identifying information to an authorisation server, to determine whether the portable battery pack is authorised for charging and/or discharging.

The activation station may be configured to be connected to a plurality of portable battery packs.

The activation station may further comprise a charge controller configured to charge the one or more cells of the portable battery pack. An advantage of the activation station having a charge controller which can charge the one or more cells of the portable battery pack is that the portable battery pack does not need its own charge controller, eliminating the additional weight and bulk of a charge controller from the portable battery pack and reducing the cost of the portable battery pack. Also, by putting the charge controller in the activation station, the charger controller may be larger, more efficient and better cooled, and therefore may be able to charge the portable battery pack more quickly and efficiently.

The charge controller may be configured to charge a plurality of portable battery packs. In this way, it is not necessary to provide an individual charge controller for each portable battery pack, reducing the cost of the activation station. Instead, a single high capacity charge controller can be provided which is more efficient and better cooled, and therefore may be able to charge the portable battery pack more quickly and efficiently.

The activation station processor may be further configured to receive a charging specification. The activation station may receive the charging specification from the portable battery pack or a server (such as the activation server). The charge controller may be configured to charge the one or more cells of the portable battery pack based on the charging specification. An advantage of the activation station processor being further configured to receive a charging specification is that the preferred charging conditions of the portable battery pack are known, thereby ensuring that optimum charging of the portable battery pack is achieved, based on the type of cells in the portable battery pack, thereby improving the lifetime of the cells and reducing the risk of failure, damage, overheating or fire.

Claims

1. A portable battery pack comprising:

an input removably connectable to an activation station for controlling discharging of the portable battery pack when the portable battery pack is subsequently disconnected and remote from the activation station;

one or more cells configured to store electrical energy; and

a processor configured to enable or disable the discharging of the one of more cells based on a discharging authorisation signal received at the input from the activation station when the input is connected to the activation station, in order to enable or disable the discharging of the portable battery pack when disconnected and remote from the activation station,

wherein discharging is enabled when the discharging authorisation signal received at the input from the activation station indicates that discharging is authorised, and discharging is disabled when the discharging authorisation signal received at the input from the activation station indicates that discharging is not authorised.

2. The portable battery pack of claim 1, wherein the processor is configured to disable discharging of the one or more cells after a period of time has elapsed, wherein the period of time is one of: a period of time since discharging of the one or more cells was enabled; a period of time since discharging of the one or more cells first began following the last time discharging of the one or more cells was enabled; or a sum of the discharge time since the last time discharging of the one or more cells was enabled.

3. The portable battery pack of either of claims 1 or 2, wherein the one or more cells are configured to be charged by a charge controller in the activation station.

4. The portable battery pack of claim 3, wherein the processor is further configured to send a charging specification to the charge controller in the activation station.

5. The portable battery pack of any preceding claim, wherein the processor is configured to send a log file containing historical usage information of the portable battery pack to the activation station, wherein the historical usage information is used to determine whether discharging should be disabled.

6. The portable battery pack of any preceding claim, wherein the processor is configured to disable discharging based on depth of discharge information received from the activation station.

7. An activation station for a portable battery pack having one or more cells configured to store electrical energy, the activation station comprising:

an output removably connectable to a portable battery pack for controlling discharging of the portable battery pack when the portable battery pack is subsequently disconnected and remote from the activation station; and

a processor configured to send, to the output, a discharging authorisation signal in order to enable or disable the discharging of the portable battery pack when disconnected and remote from the activation station.

8. The activation station of claim 7, wherein the activation station is configured to charge the one or more cells of the portable battery pack, and wherein the processor is configured to send a signal to the output indicating that charging of the one or more cells is not authorised when a desired charge level of the one or more cells is obtained, in order to prevent unauthorised charging of the one or more cells after disconnecting the portable battery pack from the activation station.

9. The activation station of either of claims 7 or 8, wherein the processor is configured to send a signal to the output indicating that discharging of the one or more cells is authorised when a desired charge level of the one or more cells is obtained.

10. The activation station of any of claims 8 to 9, wherein the processor is configured to generate a discharging authorisation signal based on authorisation information obtained from an authorisation server.

11. The activation station of any of claims 7 to 10, further comprising a charge controller configured to charge the one or more cells of the portable battery pack.

12. The activation station of claim 11, wherein the charge controller is configured to adjust the rate of charging of the one or more cells based on either: the time of day; or a desired charging time.

13. An authorisation server to store authorisation information about a portable battery pack, the authorisation server comprising:

a memory comprising authorisation information which indicates whether or not discharging the portable battery pack is authorised; and

a processor configured to:

receive a signal requesting authorisation information relating to the portable battery pack;

retrieve the authorisation information from the memory; and send the authorisation information to an activation station, which uses the authorisation information to generate a discharging authorisation signal to enable or disable discharging of the portable battery pack when disconnected and remote from the activation station.

14. The authorisation server of claim 13, wherein the processor is configured to receive a log file containing historical usage information of the portable battery pack and the processor is configured to update the authorisation information in the memory based on the log file.

15. A system comprising:

at least one portable battery pack configured according to any of claims 1 to 6; an activation station configured according to any of claims 7 to 12, and optionally an authorisation server configured according to either of claims 13 or 14.