WO2022118235A1

WO2022118235A1 - A modular battery system and a method of providing power using the battery system

Info

Publication number: WO2022118235A1
Application number: PCT/IB2021/061224
Authority: WO
Inventors: Christiaan Gerhardus ACKERMANN
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-12-02
Filing date: 2021-12-02
Publication date: 2022-06-09
Anticipated expiration: 2023-06-02
Also published as: ZA202306526B

Abstract

The invention relates to a battery module (10), a modular battery system (100) and a method (50) of providing power using the modular battery system (100). The battery system includes a plurality of interconnectable battery modules (10) including a master battery module (20). Each battery module (10, 20) includes a node communication unit for communicating with the other battery modules via Bluetooth, and a unique identifier. The method includes receiving a deed registry which comprises a list of unique identifiers of battery modules over which a user holds a deed, reading each unique identifier of connected modules (10) to form a module connection list, comparing the module connection list with the deed registry, and provided that the module connection list matches the deed registry, broadcasting an ACTIVE signal to each of the battery modules (10). However, if there is a mismatch, the battery modules hibernate which improves system security.

Description

A modular battery system and a method of providing power using the battery system

FIELD OF INVENTION

The invention relates to a modular battery system or power pack having a plurality of interconnectable battery modules. More specifically, the invention relates to a method of providing power using the battery system.

BACKGROUND OF INVENTION

Battery power packs or battery systems comprising a plurality of battery modules are increasing in popularity as more power consumers are turning to renewable power supply systems such as solar power systems. However, there are a number of drawbacks associated with these battery systems. First, individual battery modules, or the battery system as a whole, are susceptible to theft. Secondly, a skilled technician and/or tools are usually required to install and maintain the battery systems. Thirdly, some battery systems lack scalability and/or modularity, i.e. battery modules cannot easily be added to increase capacity of the battery system.

WO 2017/158568 discloses a modular battery system 50 comprising a plurality of battery modules 10 which are interconnectable by way of complementary, mating electrical connectors, in plug-and-play fashion. An advantage of this battery system 50 is that it facilitates easy connection/disconnection of individual battery modules 10 without the need of tools. Furthermore, the battery system 50 is modular and any linear or rectangular array of modules 10 can be constructed. However, the ease with which the individual battery modules 10 can be disconnected and removed makes the battery system 50 susceptible to theft. US 2019/0103641 , on the other hand, discloses a battery system including smart energy cells 106 or battery modules which are operatively removably mounted to a smart enclosure 110 which has a predetermined number of slots or bays for receiving smart energy cells 106. Each smart energy cell 106 is communicatively linked to a smart power system 108. Furthermore, each smart energy cell 106 includes a power subsystem 104 which manages communication between each of the cells and the rest of the smart power system. Each power subsystem 104 includes an authentication module 330 and a switch 318 which is open until proper authentication information is validated between the smart power system 108 and the smart energy cell 106. This authentication feature can be used to prevent theft of the smart energy cells 106, due to the fact that, in the absence of proper authentication, the cells 106 will be inutile if stolen.

A drawback associated with this battery system is increased cost, and modular complexity when upscaling the battery system. As mentioned above, the smart enclosure 1 10 has only a predetermined number of slots for receiving smart energy cells 106. Accordingly, once all slots have been filled by smart energy cells 106, additional cells cannot merely be added to the battery system. Instead, in addition to the new cells that need to be purchased, additional smart enclosures 110 also have to be purchased to accommodate the new cells. The smart enclosures then need to be electrically interconnected with the existing smart enclosure 1 10 to form a new nested stack of smart energy cells 106. In addition, a separate smart power module 1535 must be purchased to manage the nested stack of smart energy cells 106. The nested stack unnecessarily increases complexity of power management of the system and communication between the individual cells of the stack. The need for significant additional capital expenditure to facilitate upscaling of the system may make it prohibitively expensive for lower income markets. There therefore exists a need for a modular battery system which has increased ease of scalability. It is an object of the present invention to provide a battery module, modular battery system and method which overcome or at least alleviate the drawbacks discussed above.

SUMMARY OF INVENTION

According to a first aspect of the invention, there is provided a battery module which includes: a battery including a plurality of chemical cells, wherein power supply from the battery is controlled by a battery management system embedded in the battery; a housing within which the battery is housed; a first pair of electrical connectors which are mounted to the housing and are internally electrically connected to the battery by a power bus for series connection to a horizontally adjacent battery module; a second pair of electrical connectors which are also mounted to the housing and are internally electrically connected to the battery by the power bus for parallel connection to a vertically adjacent battery module; switching circuitry including at least one switch which is coupled to the power bus and is configured to interrupt power supply from the battery to one or more of the electrical connectors; and a node communication unit which is communicatively linked to one or more node communication units of adjacent battery modules and to the battery management system of the battery, wherein the battery management system is configured, upon a predetermined condition being met, to establish, for a predetermined period of time, power supply from the chemical cells to the power bus and a remainder of the battery module.

The node communication unit may be wirelessly communicatively linked to the one or more node communication units of adjacent battery modules. The node communication unit may be wirelessly communicatively linked to a master battery module or power interface module. The node communication unit may be configured wirelessly to communicate with the one or more node communication units of adjacent battery modules by way of Bluetooth communication.

The predetermined condition may be receipt, by the battery management system, of a valid authentication key associated with each slave battery module. In response to receipt of a valid authentication key, the battery management system may facilitate, for a predetermined period of time, power supply from the chemical cells of the battery to the power bus.

The node communication unit may be communicatively linked to a plurality of communication ports which are mounted to the housing. The communication ports may be integrated with the first and/or second pair of electrical connectors. Each communication port may include an infrared transceiver.

In accordance with another aspect of the invention, there is provided a modular battery system which includes: a plurality of vertically and/or horizontally interconnectable slave battery modules, each slave battery module including a node communication unit for communicating with adjacent battery modules via a communication protocol; at least one master battery module or power interface module which is connected to the slave battery modules, each slave battery module including a unique identifier and being coupled to the master battery module by way of a power bus configured to transfer power to/from the master battery module and by way of the communication node which communicatively links each slave battery module to the master battery module, wherein each slave battery module includes a battery having a plurality of chemical cells and a battery management system which is embedded in the battery and is configured to control power supply from the battery, wherein the battery management system, upon a predetermined condition being met, for a predetermined period of time is configured to switch the slave battery module to an ACTIVE state in which the battery supplies power via the power bus, wherein in an INACTIVE or HIBERNATING state power transmission from the battery via the power bus is cut off by the battery management system; and a communication device which is communicatively linked to the master battery module, wherein the master battery module is configured to: receive a user-specific battery module deed registry which comprises a list of unique identifiers of battery modules over which a user holds a deed or use right; read via the communication protocol, the unique identifier associated with each slave battery module connected to the master battery module to form a module connection list; compare the module connection list with the user-specific battery module deed registry; and broadcast, via the communication protocol, to the respective slave battery modules, an authentication key associated with each of the slave battery modules present in the module connection list and the battery module deed registry in response to which a state of each of these slave battery modules is designated as ACTIVE provided that the broadcast authentication key matches an individual slave battery module authentication key.

In the event that the broadcast authentication key does not match an individual authentication key associated with the slave battery module, the slave battery module is configured to remain in its default INACTIVE or HIBERNATING state.

The communication protocol may be a wireless communication protocol. The wireless communication protocol may be Bluetooth. The slave battery module may be a battery module as described above.

As an additional security feature, the communication device may be configured intermittently and wirelessly to authenticate the master battery module when brought within a predetermined proximity range, e.g. 10 metres, of the master battery module. If after expiry of a predetermined period of time e.g. 30 days, the communication device fails to authenticate the master battery module, the master battery module may hibernate. The implication is that if the slave battery modules and master battery module are stolen, i.e. separated by more than 10 metres for more than 30 days from the communication device, the master battery module hibernates and becomes inactive.

In accordance with yet another aspect of the invention, there is provided a method of providing power using a modular battery system, the modular battery system being connectable to a load and including: a plurality of vertically and/or horizontally interconnectable slave battery modules and at least one master battery module or power interface module which is connected to the slave battery modules, each slave battery module including a node communication unit for communicating with adjacent battery modules via a communication protocol and a unique identifier and being coupled to the master battery module by way of a power bus configured to transfer power to/from the master battery module and by way of the node communication unit which communicatively links each slave battery module to the master battery module, wherein each slave battery module includes a battery having a plurality of chemical cells and a battery management system which is embedded in the battery and is configured to control power supply from the battery, wherein the battery management system, upon a predetermined condition being met, for a predetermined period of time is configured to switch the slave battery module to an ACTIVE state in which the battery supplies power via the power bus, wherein in an INACTIVE or HIBERNATING state power transmission from the battery via the power bus is cut off by the battery management system; and a communication device which is communicatively linked to the master battery module, the method including: interconnecting, by way of the power bus, the plurality of slave battery modules to form a vertical and/or horizontal array; coupling, by way of the power bus, the master battery module to the vertical and/or horizontal array; receiving, using the master battery module, a user-specific battery module deed registry which comprises a list of unique identifiers of battery modules over which a user holds a deed or use right; reading, using the master battery module, via the communication protocol, the unique identifier associated with each slave battery module connected to the master battery module to form a module connection list; comparing, using the master battery module, the module connection list with the user-specific battery module deed registry; and broadcasting, via the communication protocol, to the respective slave battery modules, an authentication key associated with each of the slave battery modules present in the module connection list and the battery module deed registry in response to which a state of each of these slave battery modules is designated as ACTIVE provided that the broadcast authentication key matches an individual slave battery module authentication key.

In the event that the broadcast authentication key does not match the individual authentication key associated with the slave battery module, the slave battery module is configured to remain in its default INACTIVE or HIBERNATING state.

The method may include creating or populating, using the communication device, the user-specific battery module deed registry. The step of creating the user-specific battery module deed registry may include: creating a user profile; and associating or assigning unique identifiers of battery modules over which the user holds the deed or use right to the user’s profile.

The step of associating or assigning unique identifiers to the user’s profile may include: accessing, using the communication device, the user profile by way of a mobile application; and capturing, using the communication device, the unique identifier of each slave battery module in the user’s possession to form the battery module deed registry. The method may further include forwarding, using the communication device, the battery module deed registry to the master battery module. The communication device may be a smartphone. Accordingly, capturing the unique identifier may include scanning, using the smartphone, the unique identifier of each slave battery module.

The modular battery system may further include a remote server which is communicatively linked to the communication device and/or the master battery module. The user-specific battery module deed registry may be stored on the remote server. The method may include receiving, at the master battery module, a HIBERNATION signal designating the state of the modular battery system to “HIBERNATING”. The signal may be received from the remote server or from the communication device. The method may include forwarding, using the master battery module, the HIBERNATION signal to each of the slave battery modules via the communication protocol.

The method may further include: receiving, at the master battery module, a selection of a security level of the modular battery system. The modular battery system may have a user- selectable high, medium and low security level. Provided the user has full ownership rights of the modular battery system, the user may be able to select and/or switch between any of the security levels of the modular battery system using the mobile application running on the smartphone.

The modular battery system may be a solar battery system. Accordingly, a plurality of solar panels may be coupled to the master battery module in order to energise the battery modules.

In the event that a battery module is removed or added to the modular battery system, the method may include updating the module connection list and recomparing it with the battery module deed registry to determine the state of the modular battery system.

If the predetermined period of time, e.g. 5 minutes, has expired and a fresh authentication key has not been received by the battery management system of the slave battery module then it will default to its HIBERNATING or INACTIVE state.

Each battery module, including the master battery module, may include a node communication unit. The node communication unit may be communicatively linked to adjacent battery modules by way of the communication protocol. The node communication unit may include a transceiver for bidirectional communication. The transceiver may be an infrared transceiver. Alternatively, or in addition, the node communication unit may be configured for Bluetooth communication. The communication protocol may therefore be Bluetooth.

The method may further include establishing node communication between the master battery module and the individual slave battery modules by allocating, using a master communication unit of the master battery module, a unique communication address to each of the slave battery modules connected to the master battery module.

The method may include: receiving, at the node communication unit of each slave battery module via the communication protocol, a unique communication address allocation from the master communication unit of the master battery module.

The method may include: intermittently receiving, at the node communication unit of each slave battery module, an encrypted authorisation key; decrypting the authorisation key; and comparing the decrypted key with a stored value; and, if the decrypted key does not match the stored value, designating the state of the slave battery module as HIBERNATING or INACTIVE and disconnecting the slave battery module from the power bus.

The invention extends to a non-transitory computer-readable storage medium having instructions stored thereon which, when executed by a computing system, enable the computing system to perform any one of the method steps described above.

BRIEF DESCRIPTION OF DRAWINGS

The invention will now be further described, by way of example, with reference to the accompanying schematic drawings.

In the drawings:

Figure 1 shows a three-dimensional longitudinal section of an exemplar housing of a battery module in accordance with one aspect of the invention;

Figure 2.1 shows a schematic representation of internal circuitry of a first embodiment of the battery module;

Figure 2.2 shows another schematic representation of the internal circuitry of a second embodiment of the battery module;

Figure 3 shows a functional block diagram of a modular battery system in accordance with another aspect of the invention;

Figure 4 shows a flow diagram of a method of providing power using the modular battery system; and

Figure 5 shows a high-level schematic block diagram of the battery module.

DETAILED DESCRIPTION OF AN EXAMPLE EMBODIMENT

The following description of the invention is provided as an enabling teaching of the invention. Those skilled in the relevant art will recognise that many changes can be made to the embodiments described, while still attaining the beneficial results of the present invention. It will also be apparent that some of the desired benefits of the present invention can be attained by selecting some of the features of the present invention without utilising other features. Accordingly, those skilled in the art will recognise that modifications and adaptations to the present invention are possible and can even be desirable in certain circumstances, and are a part of the present invention. Thus, the following description is provided as illustrative of the principles of the present invention and not a limitation thereof.

In Figure 1 , reference numeral 10 refers generally to a battery module in accordance with the invention. In Figures 2.1 and 2.2 reference numerals 10.1 and 10.2 refer to first and second embodiments of the battery module 10, respectively. The same reference numerals will be used to describe similar parts of the first and second embodiments of the battery modules 10.1 and 10.2. Figure 5 illustrates a high-level schematic block diagram of the battery module 10.2. The battery module 10.2 includes a battery 11 , e.g. a lithium ion 12 V battery comprising a plurality of cells 11.1 and an embedded battery management system 11 .2 which is configured to control operation of the cells 11.1. Alternatively, the battery may take the form of any other suitable energy source such as supercapacitors that can vary according to evolving battery technologies, including lithium ion-sulphur, carbon nanotubes, or potentially even next generation fuel-cells. The battery 11 is housed within a housing 12. The housing 12 is configured such that the battery module 10 is easily vertically and/or horizontally interconnectable with adjacent battery modules 10 in plug-and-play fashion without requiring any tools or technical expertise. To prevent incorrect installation the housing 12 has a pair of opposing planar sides, a convexly curved top 12.1 and an opposing, complemental concavely curved bottom 12.2, a convexly curved front end 12.3 and a complemental concavely curved rear end 12.4. Complementary male and female mating formations 13.1 , 13.2, 13.3, 13.4 on the front and rear ends, and top and bottom respectively facilitate mechanical interconnection between adjacent battery modules 10.

Mating formations 13.3 and 13.4 each comprise a pair of electrical connectors which are internally electrically connected to the battery 11 by way of a power bus 14 for series connection to horizontally adjacent battery modules. On the other hand, mating formations 13.1 and 13.2 each also comprise a pair of electrical connectors which are also internally electrically connected to the battery 11 via the power bus 14 for parallel connection to vertically adjacent battery modules. The battery module 10 further includes switching circuitry including at least one switch 15 which is coupled to the power bus 14 and is configured to interrupt power supply from the battery 11 to one or more of the electrical connectors. In addition to the switching circuitry, the battery management system 11.2 provided inside of, or embedded in, the battery 1 1 is configured to either interrupt or establish power supply to components connected to the battery 1 1 depending on receipt of a valid authentication key, as an additional security measure. In other words, the battery management system 11 .2 may intermittently require receipt of an authorisation key for the battery 11 to remain active. If after a predetermined period of time, e.g. 5 minutes, a valid authorisation key is not received by the battery management system 11.2, the battery 1 1 automatically hibernates. When hibernating, the battery management system 11 .2 of the battery 11 cuts off power supply from the cells 1 1.1 to all components connected to the battery 1 1. This additional security measure discourages theft of the battery 11 due to the fact that it is inutile when not validly authenticated with the correct authorisation key. This serves as a theft deterrent as, even if the battery module 10 is deconstructed, the battery 1 1 cannot be used or repurposed on its own due to the authorisation requirement of the embedded battery management system 11 .2. Exact electrical connection of the respective connectors with the switching circuitry will not be described in detail here. Reference can be made to WO 2017/158568 for a discussion in this regard.

Referring now to Figure 2.1 , the battery module 10.1 includes a node communication unit 17.1. In this first embodiment, the node communication unit 17.1 takes the form of a microcontroller which is communicatively linked to a plurality of communication ports 18 which are mounted to the housing 12. These communication ports 18 are integrated into the respective mating formations 13. When the mating formations 13 engage those of adjacent battery modules, the communication ports 18 are communicatively linked to those of the adjacent battery module. Furthermore, the node communication unit 17.1 is coupled to the battery 11 which is configured, upon expiry of the predetermined period of time from last receipt of the authorisation key, to cut off power supply to the power bus 14. Each communication port 18 may comprise an infrared transceiver which is coupled to the node communication unit 17.1 for bidirectional communication. Upon a predetermined condition being met, which may comprise receipt of a valid authentication key by the battery management system 11 .2, the battery 11 remains in an active state. A hibernation signal may be received by the node communication unit 17.1 and may be passed on to the battery 11 .

Referring now to Figure 2.2, the battery module 10.2 includes a node communication unit 17.2 which is configured for wireless communication with node communication units of other battery modules 10 in close proximity as well as with a master battery module or power interface module 20 (see Figure 3). Preferably, the node communication unit 17.2 is configured for wireless communication via the Bluetooth communication protocol. Furthermore, the node communication unit 17.2 is coupled to the battery 11. Upon the predetermined condition being unmet, i.e., in the absence of receipt of a valid authentication key after expiry of a predetermined period of time, the battery management system 11.2 is configured to cut off power supply from the cells 11.1. The node communication unit 17.2 is also configured to receive a hibernation signal from an external communication device, for example from a smartphone or from the master battery module 20. The node communication unit 17.2 is configured to pass the hibernation signal on to the battery 11 .

Reference is now made to Figure 3, where reference numeral 100 refers generally to a modular battery system in accordance with another aspect of the invention. The modular battery system 100 includes a plurality of the battery modules 10 described above, configured as slave battery modules, horizontally and vertically interconnected as shown in Figure 3 to form a series/parallel 4x4 array. The modular battery system 100 also includes the master battery module 20 or power interface module which is connected to the slave battery modules 10 as shown. The master battery module 20 may take the form of an inverter and power interface module to which a load may be connected. Each slave battery module 10 has a unique identifier, i.e. a serial number which is stored to its node communication unit 17. In addition, by virtue of being part of the array of connected battery modules, each slave battery module 10 is coupled to the master battery module 20 by the respective power buses 14 of the slave battery modules and, accordingly, is configured to transfer/receive power to/from the master battery module 20. Furthermore, the node communication units 17.2 of the slave battery module 10.2 are wirelessly communicatively linked via Bluetooth to another and to the master battery module 20. The master battery module 20 includes a master communication unit and a load switch (not shown). The master communication unit may control the load switch to switch the modular battery system 100 between an ACTIVE state in which the master battery module 20 is electrically coupled to the load (not shown) and is configured to deliver power from the slave battery modules 10 to the load, and an INACTIVE or HIBERNATING state in which power transmission to the load is cut off. Furthermore, or in addition, the master communication unit of the master battery module 20 may be configured to send out periodic signals or authentication keys to authenticate the slave battery modules 10 connected thereto. The master communication unit is configured to receive a reply from the slave battery module 10 with the serial number of the node communication unit 17.2. If the serial number does not match a battery module deed registry, the master communication unit cannot transmit the authentication key to that slave battery module with the unrecognised serial number. Resultantly, if the slave battery module does not intermittently receive its predetermined authentication key from the master communication unit, the slave battery modules goes into hibernation.

The modular battery system 100 further includes at least one communication device, which may be in the form of a smartphone 30, which is communicatively linked to the master communication unit of the master battery module 20, preferably via Bluetooth or similar wireless communication protocols. The modular battery system 100 further includes a remote server 40 which is communicatively coupled to the smartphone 30 via a telecommunications network.

As an additional security feature, the smartphone 30 may be configured intermittently and wirelessly to authenticate the master battery module 20 when brought within a predetermined proximity range, e.g. 10 metres, of the master battery module 20. If after expiry of a predetermined period of time e.g. 30 days, the smartphone 30 has failed to authenticate the master battery module 20, the master battery module 20 becomes inactive and hibernates. The implication is that if the slave battery modules 10 and master battery module 20 are stolen, i.e. separated by more than 10 metres for more than 30 days from the smartphone, the master battery module 20 hibernates and becomes inactive.

In Figure 4, reference numeral 50 refers generally to a method of providing power using the modular battery system 100. In order to use the modular battery system 100, a user may either purchase the battery modules 10, 20 from a retailer or enter into a user or service agreement with a service provider through which the user acquires the right to use the battery system 100. It will be appreciated that, owing to its modularity, a host of different series and/or parallel battery module arrangements or arrays may be created by simply interconnecting battery modules 10 via the complementary mating formations 13. That said, once having connected the battery modules 10 together to form the horizontal and/or vertical array, an initial commissioning step needs to be taken, as a security measure, before a user can enjoy the benefit of the modular battery system 100. Commissioning includes verifying that the user is entitled to use the battery system 100 before enabling the system 100. Commissioning may include geotagging of the geolocation of the battery system 100 using the smartphone 30. To this end, if the battery system 100 has been installed in a location where there is no internet connectivity, the smartphone 30 may serve as a data carrier until connectivity is re-established and the data can be uploaded.

To commission the battery system 100, the user is required to download 51 a mobile application and to install it onto their smartphone 30. The user is then required to create 52 a user profile and to log into their profile. Once logged in, the method 50 includes scanning 53 the serial numbers of the individual battery modules 10, 20 in his/her possession, or forming part of their battery array, using the smartphone 30, to associate or assign the individual battery modules 10 to their profile. The serial numbers may be represented on the battery modules 10, 20 in the form of QR codes which can be easily scanned using the smartphone’s QR code scanner. Once scanned, the application populates 54 a battery module deed registry specific to the user profile using the scanned serial numbers. The deed registry is then forwarded, via Bluetooth, to the master communication unit of the master battery module 20. Accordingly, the method 50 includes receiving 55, by the master battery module 20, the user-specific battery module deed registry comprising a list of the unique identifiers, i.e., serial numbers of battery modules 10 over which the user holds the deed or use right.

The method further includes establishing node communication between the master battery module 20 and the individual slave battery modules 10 connected thereto. This includes polling 56 the slave battery modules 10 by forwarding a broadcast message either via the communication ports 18 to the node communication units 17.1 or via Bluetooth to the node communication units 17.2 of each of the slave battery modules 10.1 , 10.2 respectively. In this manner the master battery module discovers all slave battery modules 10 connected to or forming part of the array. The master battery module 20 then allocates 57, using the master communication unit of the master battery module 20, a unique communication address to each of the slave battery modules 10 connected thereto. Furthermore, the method 50 includes reading 58, using the master battery module 20, via the communication protocol, the unique identifier associated with each slave battery module 10 connected to the master battery module 20 to form a module connection list.

Once the module connection list has been formed, the master battery module 20 is configured to compare the module connection list with the user-specific battery module deed registry in an attempt to establish whether or not the user is authorised to make use of the battery modules 10, 20 forming part of the battery system 100. The module connection list also includes a unique identifier associated with the master battery module 20. Provided that the module connection list matches 59 or is found as forming part of the userspecific battery module deed registry, the master battery module broadcasts 60 an ACTIVE signal to all of the slave battery modules 10 found in the deed registry. The ACTIVE signal may take the form of individual authentication keys associated with each slave battery module 10. The keys are communicated to the node communication units 17.2 which in turn passes it on to the respective battery management systems 11 .2 which results in all the validly authenticated battery management systems 11 .2 of the batteries 1 1 of the slave battery modules 10 supplying power to the load. The load switch of the master battery module 20 may also be closed. Hence a state of the modular battery system 100 is designated as ACTIVE 61 .

In the event that the module connection list does not match, or does not appear in, or form part of the user-specific battery module deed registry, the master battery module 20 will be unable to authenticate those slave battery modules 10 who’s unique identifiers do not appear in the deed registry and, accordingly, the battery management systems 11 .2 of those battery modules 10 will initiate hibernation which cuts them off from the rest of the system 100.. The load switch may also be opened which interrupts power supply to the load. Hence the state of the modular battery system 100 may be designated as HIBERNATING 63 or partially hibernating.

It will be appreciated that the user-specific battery module deed registry may be stored on the remote server 40. Also, as a remote override function in case of an emergency, a hibernation signal designating the state of the modular battery system to “HIBERNATING” may be sent to the master battery module 20 from either of the remote server 40 or the smartphone 30.

The modular battery system 100 may include a solar power charging system. Accordingly, a plurality of solar panels (not shown) may be coupled to the master battery module 20 in order to energise or charge the battery modules 10. The battery modules 10 may also be charged via mains power connection.

In the event that a battery module 10 is removed or added to the modular battery system 100, the module connection list will be updated by the master battery module 20 through intermittent polling or reading 58 of the serial numbers of the slave battery modules 10 by the master battery module. Accordingly, the method 50 includes intermittently, e.g. every 5 minutes recomparing the module connection list with the battery module deed registry to determine the state of the modular battery system 100. Depending on user- selectable security settings, the battery system 100 may go into hibernation when a battery module 10 is removed or disconnected, added or if an intermittent authentication step fails.

To prevent module theft, each battery module 10 must be intermittently authenticated. This authentication step is performed at predefined time intervals, i.e. every 5 minutes and includes: receiving, at the node communication unit 17 of each slave battery module 10, an encrypted authorisation key; decrypting the authorisation key, using the node communication unit 17 or battery management system 11 .2; and comparing the decrypted key with a stored value; and, if the decrypted key does not match the stored value, disconnecting, using the battery management system 11 .2, the slave battery module 10 from the power bus 14 and from the rest of the battery system 100. Disconnecting may imply designating the state of the battery module 10 as “HIBERNATING”. The battery module 10 will remain in its hibernating state until the correct encrypted authorisation key is received by the node communication unit 17 and/or the battery management system 11 .2. This is an additional security feature which will discourage theft of the individual battery modules 10 because the modules 10 will hibernate if the correct encrypted authorisation key is not received after a predetermined period of time has elapsed, e.g. 5 minutes. If the battery management system has disconnected the cells 11.1 by entering hibernation, the battery 11 itself becomes inutile until the correct encrypted authorisation key is received from the node communication unit 17. The node communication unit 17 is therefore directly coupled to the battery 11.

The battery system 100 has been designed to accommodate the purest, simplest form of modularity, i.e. no extra components or docking stations are required for the modules 10 to connect to one another. The system has been designed such that the modules can be individually added to the stack in any combination or configuration that is allowed by the system design constraints. The modules automatically connect into series and parallel depending on the stacking thereof.

The node communication unit 17 may consist of a 32bit processor based around an STM32 range of microcontrollers or similar. Each slave battery module has an identical design. The microcontroller has an I2C interface to the battery. The battery provides a low current voltage supply to the microcontroller. The supply is provided to the battery via a connector between the battery and controller board. The connector has four wires: VCC, SDA, SCL and GND. The I2C communication provides the channel whereby the master communication unit can read the relevant module statistics and “poll” the modules periodically to keep it connected to the system.

The I2C interface shall run in standard mode (100kHz). The master communication unit or node communication unit is the I2C master. Each battery management system shall have a register map of values. The master communication unit or node communication unit shall read or write values to the register map via an index register. The node communication unit first writes the index address - this sets up the starting address for the next I2C transaction. The node communication unit then can read/write a maximum of 64 bytes from the battery management system. After each byte read/written the index register is incremented by 1 byte.

Battery Controller Register map

Table 1

Each node communication unit is connected to every other node communication unit in the stack via the infrared communication ports 18 or the via wireless communication protocol. All node communication units are initially non-configured and listen to broadcast messages. Broadcast messages are messages that have a column and row address set to 0xFF,0xFF (addresses are 8 bits). Messages are sent from the master communication unit (node installed in the inverter). The master poll’s all node communication units in the chain. The node communication units only send data back to the master when polled. The master address is 0x00, 0x00. The master communication unit enters a discover stage and sends a broadcast to every node communication unit. The broadcast will reset each node’s logical address. The master then starts a discover phase where it assigns each node a logical address. The first node in the chain is assigned the address 0x01 ,0x01 and once the address has been assigned it passes any address assign commands through its East-West interface or North-South interface dependent on its own location in the stack. In this manner each node in the combined stack is assigned a logical address based on its row and column location in the composite battery stack. Once each node has been assigned a logical address the master communication unit can address each node communication unit periodically to obtain SOC (State of Charge), SOH (State of Health) and temperature values. Communication between the master communication unit and each individual node communication unit is uniquely encrypted using a combination of the module’s serial number and message digest and a seed. This mechanism is to prevent “sniffing” or eavesdropping of data being passed between the nodes.

A core focus area of development has been managing the risk of theft of the batteries/modules 10. If any node communication unit or battery management system of a battery module fails to communicate with the master communication unit then that battery module will automatically hibernate.

Every 5 minutes, the master battery module 20 is required to write a series of bytes or an authentication key to the battery management system of the slave battery modules 10. Failure to write a valid authentication key or sequence of bytes would result in the battery management system interrupting power supply and shutting off power to the connectors and putting the module into hibernation. The only way for the module to exit the hibernation state is for a valid authentication key or sequence of bytes to be written to the address associated with the battery management system of the module 10. After production of the module a one-time programmed (OTP) authentication key is written to the battery management system of the battery module, via the I2C interface. This authentication key is generated and is stored on the server 40. The module serial number is then put through a XOR logic function using the key (which is not stored on the node controller) and written to the authentication mechanism address of the battery management system. The battery management system decrypts the received signal by performing the XOR logic function with the battery serial number and compares the key with the stored key. If the key does not match the write is ignored. This requires that the correct authentication key must be written to the battery modules every 5 minutes to prevent the battery modules from going into hibernation.

The time between authentication can be lengthened as a function of the system installation life. The longer the battery system has been combined without any of the batteries being removed, the longer the time period can be between authentication.

SOH, SOC and temperature are constantly monitored on each module and this information is sent to the master communication unit via the node communication units 17. This information is sent to the smartphone 30 which then loads it onto the server 40.

The Applicant believes that the battery system 100 and method 50 of providing power using the system 100 has increased modularity when compared to existing systems owing to its plug-and-play functionality. Increased modularity necessitates increased security features which the system 100 provides in the form of intermittent module authentication and user rights management through the creation of battery module deed registries associated with user’s profiles via the mobile application. The system 100 also provides for improved inter-node communication such that it automatically recognises when battery modules 10 are added and removed and the master battery module is able effectively to establish communication between all the individual battery modules 10, including newly added battery modules by discovering and polling of the battery modules 10.

Claims

23 CLAIMS:

1 . A battery module which includes: a battery including a plurality of chemical cells, wherein power supply from the battery is controlled by a battery management system embedded in the battery; a housing within which the battery is housed; a first pair of electrical connectors which are mounted to the housing and are internally electrically connected to the battery by a power bus for series connection to a horizontally adjacent battery module; a second pair of electrical connectors which are also mounted to the housing and are internally electrically connected to the battery by the power bus for parallel connection to a vertically adjacent battery module; switching circuitry including at least one switch which is coupled to the power bus and is configured to interrupt power supply from the battery to one or more of the electrical connectors; and a node communication unit which is communicatively linked to one or more node communication units of adjacent battery modules and to the battery management system of the battery, wherein the battery management system is configured, upon a predetermined condition being met, to establish, for a predetermined period of time, power supply from the chemical cells to the power bus and a remainder of the battery module.

2. The battery module as claimed in claim 1 , wherein the node communication unit is wirelessly communicatively linked to the one or more node communication units of adjacent battery modules.

3. The battery module as claimed in claim 2, wherein the node communication unit is wirelessly communicatively linked to a master battery module.

4. The battery module as claimed in claim 2 or 3, wherein the node communication unit is configured wirelessly to communicate with the one or more node communication units of adjacent battery modules by way of Bluetooth communication.

5. The battery module as claimed in any one of the preceding claims, wherein the predetermined condition is receipt, by the battery management system, of a valid authentication key associated with each slave battery module in response to which the battery management system facilitates, for a predetermined period of time, power supply from the chemical cells of the battery to the power bus.

6. The battery module as claimed in claim 1 , wherein the node communication unit is communicatively linked to a plurality of communication ports which are mounted to the housing, the communication ports being integrated with the first and/or second pair of electrical connectors.

7. A modular battery system which includes: a plurality of vertically and/or horizontally interconnectable slave battery modules, each slave battery module including a node communication unit for communicating with adjacent battery modules via a communication protocol; at least one master battery module which is connected to the slave battery modules, each slave battery module including a unique identifier and being coupled to the master battery module by way of a power bus configured to transfer power to/from the master battery module and by way of the communication node which communicatively links each slave battery module to the master battery module, wherein each slave battery module includes a battery having a plurality of chemical cells and a battery management system which is embedded in the battery and is configured to control power supply from the battery, wherein the battery management system, upon a predetermined condition being met, for a predetermined period of time is configured to switch the slave battery module to an ACTIVE state in which the battery supplies power via the power bus, wherein in an INACTIVE or HIBERNATING state power transmission from the battery via the power bus is cut off by the battery management system; and a communication device which is communicatively linked to the master battery module, wherein the master battery module is configured to: receive a user-specific battery module deed registry which comprises a list of unique identifiers of battery modules over which a user holds a deed or use right; read via the communication protocol, the unique identifier associated with each slave battery module connected to the master battery module to form a module connection list; compare the module connection list with the user-specific battery module deed registry; and broadcast, via the communication protocol, to the respective slave battery modules, an authentication key associated with each of the slave battery modules present in the module connection list and the battery module deed registry in response to which a state of each of these slave battery modules is designated as ACTIVE provided that the broadcast authentication key matches an individual slave battery module authentication key.

8. The modular battery system as claimed in claim 7, wherein, in the event that the broadcast authentication key does not match the individual authentication key associated with the slave battery module, the slave battery module is configured to remain in its default INACTIVE or HIBERNATING state.

9. The modular battery system as claimed in claim 7 or 8, wherein the communication protocol is a wireless communication protocol.

10. The modular battery system as claimed in any one of claims 7 to 9, wherein the slave battery module is a battery module as claimed in any one of claims 1 to 5.

11. The modular battery system as claimed in any one of claims 7 to 10, wherein, as an additional security feature, the communication device is configured intermittently and wirelessly to authenticate the master battery 26 module when brought within a predetermined proximity range of the master battery module such that, if after expiry of a predetermined period of time, the communication device fails to authenticate the master battery module, the master battery module hibernates.

12. A method of providing power using a modular battery system, the modular battery system being connectable to a load and including: a plurality of vertically and/or horizontally interconnectable slave battery modules and at least one master battery module which is connected to the slave battery modules, each slave battery module including a node communication unit for communicating with adjacent battery modules via a communication protocol and a unique identifier and being coupled to the master battery module by way of a power bus configured to transfer power to/from the master battery module and by way of the node communication unit which communicatively links each slave battery module to the master battery module, wherein each slave battery module includes a battery having a plurality of chemical cells and a battery management system which is embedded in the battery and is configured to control power supply from the battery, wherein the battery management system, upon a predetermined condition being met, for a predetermined period of time is configured to switch the slave battery module to an ACTIVE state in which the battery supplies power via the power bus, wherein in an INACTIVE or HIBERNATING state power transmission from the battery via the power bus is cut off by the battery management system; and a communication device which is communicatively linked to the master battery module, the method including: interconnecting, by way of the power bus, the plurality of slave battery modules to form a vertical and/or horizontal array; coupling, by way of the power bus, the master battery module to the vertical and/or horizontal array; receiving, using the master battery module, a user-specific battery module deed registry which comprises a list of unique identifiers of battery modules over which a user holds a deed or use right; 27 reading, using the master battery module, via the communication protocol, the unique identifier associated with each slave battery module connected to the master battery module to form a module connection list; comparing, using the master battery module, the module connection list with the user-specific battery module deed registry; and broadcasting, via the communication protocol, to the respective slave battery modules, an authentication key associated with each of the slave battery modules present in the module connection list and the battery module deed registry in response to which a state of each of these slave battery modules is designated as ACTIVE provided that the broadcast authentication key matches an individual slave battery module authentication key.

13. The method as claimed in claim 12, wherein, in the event that the broadcast authentication key does not match the individual authentication key associated with the slave battery module, the slave battery module is configured to remain in its default INACTIVE or HIBERNATING state.

14. The method as claimed in claim 12 or 13, which includes creating or populating, using the communication device, the user-specific battery module deed registry, wherein, the step of creating the user-specific battery module deed registry includes: creating a user profile; and associating or assigning unique identifiers of battery modules over which the user holds the deed or use right to the user’s profile.

15. The method as claimed in claim 14, wherein the step of associating or assigning unique identifiers to the user’s profile includes: accessing, using the communication device, the user profile by way of a mobile application; and capturing, using the communication device, the unique identifier of each slave battery module in the user’s possession to form the battery module deed registry. 28

16. The method as claimed in claim 15, wherein capturing the unique identifier includes scanning, using a smartphone, the unique identifier of each slave battery module and forwarding, using the smartphone, the battery module deed registry to the master battery module.

17. The method as claimed in any one of claims 12 to 16, wherein the modular battery system further includes a remote server which is communicatively linked to the communication device and/or the master battery module, the user-specific battery module deed registry being stored on the remote server, the method including: receiving, at the master battery module, a HIBERNATION signal designating the state of the modular battery system to “HIBERNATING”, the signal being received from the remote server or from the communication device; and forwarding, using the master battery module, the HIBERNATION signal to each of the slave battery modules via the communication protocol.

18. The method as claimed in any one of claims 12 to 17, which includes: receiving, at the master battery module, a selection of a security level of the modular battery system.

19. The method as claimed in any one of claims 12 to 18, wherein, in the event that a battery module is removed or added to the modular battery system, the method includes updating the module connection list and recomparing it with the battery module deed registry to determine the state of the modular battery system.

20. The method as claimed in any one of claims 12 to 19, which includes establishing node communication between the master battery module and the individual slave battery modules by allocating, using a master communication unit of the master battery module, a unique communication address to each of the slave battery modules connected to the master battery module. 29

21 . The method as claimed in claim 20, which includes: receiving, at the node communication unit of each slave battery module via the communication protocol, a unique communication address allocation from the master communication unit of the master battery module.

22. The method as claimed in claim 21 , which includes: intermittently receiving, at the node communication unit of each slave battery module, an encrypted authorisation key; decrypting the authorisation key; and comparing the decrypted key with a stored value; and, if the decrypted key does not match the stored value, designating the state of the slave battery module as HIBERNATING or INACTIVE and disconnecting the slave battery module from the power bus.

23. A non-transitory computer-readable storage medium having instructions stored thereon which, when executed by a computing system, enable the computing system to perform any of the methods as claimed in any one of claims 12 to 22.