The present disclosure relates to the field of battery technology and energy cells and discloses solutions for determining a position of a battery cell within a battery system comprising a plurality of battery cells. In particular, embodiments of the disclosure relate to a method and a system for determining a position of a battery cell within a battery system comprising a plurality of battery cells.
Battery systems, comprising a plurality of battery cells, are used in a wide range of modern electric power applications. For example, they are used to power electric vehicles, they are used in industrial power applications, in transportation, and in commercial applications such as powering of modern electronic devices. Given the relatively high-power demands of such applications, a battery system often comprises a plurality of battery cells coupled together to achieve the required power output. The battery cells may be coupled together to form a battery pack, and the battery system may comprise one or more battery packs.
It is common to connect a battery system to a battery management system (BMS), configured to ensure that the battery system operates within its safe operating area. The safe operating area is defined as the voltage and current conditions under which the battery system is expected to operate without self-damage. For further details, the interested reader is directed to the following Wikipedia website: https://en.wikipedia.org/wiki/Battery management system.
In certain known applications, performance characteristics of the battery cells within the battery system may be monitored, to identify potentially faulty operation of cells within the battery system before a catastrophic fault occurs. The severity of the potential fault may be dependent on the position of the associated cell within the battery system. This is particularly true where the fault is associated with overheating, or a leak of battery fluids or gas. Depending on the position of the cell within the battery system, the fault may potentially provoke a catastrophic chain reaction. For example, an overheating cell located centrally within a battery system, in contact with adjacent cells on all its surfaces, poses a greater risk of causing a chain reaction, than an overheating cell located near a corner of the battery system in physical contact with a single cell. It is therefore important to know the relative positions of the battery cells comprised within a battery system.
As a safety precaution, since it is not always known how to determine the position of individual cells in a battery system, and the position of a faulty cell, it is common to replace the entire battery system, when a fault is identified in a battery cell within the battery system. This often also results in some individual cells within the battery system, which are otherwise functional, and operating normally, to be discarded. This results in significant waste of functional cells, due to the inability to determine the locations of individual cells within the battery system.
In the prior art systems of
A shortcoming of the prior art system of
It is an object of at least some embodiments of the present disclosure to address one or more shortcomings of the prior art systems, and to provide an improved solution for determining the position of individual battery cells within battery packs and systems. At least some of the disclosed embodiments may be deployed in use to identify the locations of potentially faulty cells for servicing and/or replacement, and/or to complement battery cell diagnostics.
In accordance with an aspect of the disclosure there is provided a method of determining a position of a battery cell within a battery system comprising a plurality of battery cells. Each battery cell has a unique identifier (ID), and each battery cell may be configured to experience a change in voltage when an electrical stimulus is applied to the battery cell. The method may comprise: receiving a first signal associated with a first battery cell experiencing a change in voltage due to an electrical stimulus applied to the battery cell; obtaining the unique ID associated with the first battery cell; determining the position of the first battery cell, based on the received first signal associated with the first battery cell; and associating the determined position with the obtained unique ID of the first battery cell.
In accordance with some embodiments each battery cell comprised within the battery system comprises an electrical stimulus, the electrical stimulus having an active state in which the electrical stimulus causes a change in the voltage of the associated battery cell it is connected to.
The method may further comprise receiving the first signal from a voltage measurement device connected to the first battery cell when the associated electrical stimulus is in the active state. In some embodiments the voltage measurement device may be located external to the battery system and may be configured to change the battery cell it is connected to by varying its position relative to the battery system, and the method may further comprise the steps of: determining if the battery cell the voltage measurement device is connected to is experiencing a change in voltage; changing the battery cell the voltage measurement device is connected to if no change in voltage is determined, by varying the position of the voltage measurement device relative to the battery system; and iteratively repeating the determining and changing steps until the voltage measurement device measures the change in voltage experiences by the first battery cell when connected to the first battery cell.
In accordance with some embodiments, each battery cell comprised within the battery system comprises a voltage measurement device, the voltage measurement device configured to measure a change in voltage experienced by the associated battery cell when a stimulus is applied to the battery cell by an electrical stimulus device connected to the associated battery cell. The method may comprise: receiving, from the electrical stimulus device when connected to the first battery cell, the first signal comprising first position information associated with the position of the electrical stimulus device connected to the first battery cell, the first position information comprising information associated with a position of the electrical stimulus device relative to the first battery cell; and determining the position of the first battery cell within the battery system, based on the first position information. The electrical stimulus device may be located external to the battery system and may be configured to change its position relative to the plurality of battery cells in order to connect to a different one of the battery cells, and cause a change in voltage in the connected battery cell.
In accordance with some embodiments, the electrical stimulus may comprise an electrical load having an active state in which the electrical load draws current from the associated battery cell it is connected to, and an inactive state in which current is not drawn from the associated battery cell.
In accordance with some embodiments, the electrical stimulus may comprise a charger having an active state in which the charger charges the associated battery cell it is connected to.
In accordance with another aspect of the disclosure, a processor for determining a position of a battery cell within a battery system comprising a plurality of battery cells, each battery cell having a unique ID, and each battery cell configured to experience a change in voltage when an electrical load is applied to the battery cell. The processor may be configured to: receive a first signal associated with a first battery cell experiencing a change in voltage due to an electrical load applied to the battery cell; obtain the unique ID associated with the first battery cell; determine the position of the first battery cell, based on the received first signal associated with the first battery cell; and associate the determined position with the obtained unique ID of the first battery cell.
In accordance with another aspect of the disclosure there is provided a method of determining a position of a battery cell within a battery system comprising a plurality of battery cells, each battery cell having a unique ID, and each battery cell comprising a processing device configured to emit an activation signal, the battery system being assembled in accordance with a predefined assembly sequence. The method may comprise: receiving an activation signal associated with each one of the plurality of battery cells comprised within the battery system, each activation signal enabling the unique ID of the associated battery cell to be obtained; associating a time coordinate with each received activation signal; determining an activation sequence defining an order in which the processing devices associated with the plurality of battery cells are activated based on the time coordinate associated with each received activation signal and the unique ID associated with each battery cell; and determining the position of each battery cell based on the activation sequence and the predefined assembly sequence. The predefined assembly sequence may define the physical order in which the plurality of battery cells are positioned within the battery system, and the method may further comprise determining the position of each battery cell by associating the activation sequence with the physical order in which the plurality of battery cells are positioned within the battery system. The predefined assembly sequence may define the physical order in which the plurality of battery cells are positioned within the battery system.
In accordance with some embodiments, the activation signal may be emitted when the processing device first activates during assembly of the battery system, and the method may further comprise: determining a time of receipt associated with each received activation signal; and determining the activation sequence based on the time of receipt associated with each received activation signal and the unique ID associated with each battery cell. Determining the time of receipt may comprise using a clock to measure the time of receipt of the activation signal.
In accordance with some embodiments, each processing device may comprise a clock configured to begin measuring time when the processing device first activates during assembly of the battery system. The method may further comprise: receiving the time coordinate, wherein a different time coordinate is associated with each processing device, the time coordinate being indicative of a time laps occurring between first activation of the associated processing device and transmission of the activation signal associated with each one of the plurality of battery cells; determining a time difference between the time coordinates associated with each received activation signal; and determining the activation sequence defining the order in which the processing devices associated with the plurality of battery cells first activate based on the determined time different between the time coordinates associated with each received activation signal.
In accordance with yet a further aspect of the disclosure, there is provided a processor for determining a position of a battery cell within a battery system comprising a plurality of battery cells, each battery cell having a unique ID, and each battery cell comprising a processing device configured to emit an activation signal, the battery system being assembled in accordance with a predefined assembly sequence. The processor may be configured to: receive an activation signal associated with each one of the plurality of battery cells comprised within the battery system, each activation signal enabling the unique ID of the associated battery cell to be obtained; associate a time coordinate with ach received activation signal; determine an activation sequence defining an order in which the processing devices associated with the plurality of battery cells are activated based on the time coordinate associated with each received activation signal and the unique ID associated with each battery cell; and determine the position of each battery cell based on the activation sequence and the predefined assembly sequence.
In accordance with yet a further aspect of the disclosure there is provided a battery management system (BMS) comprising any one of the aforementioned processors.
Yet a further aspect of the disclosure comprises a computer program product comprising computer-executable instructions, which when executed by one or more processor, cause the one or more processors to perform any one of the aforementioned methods.
In accordance with yet a further aspect of the disclosure, there is provided a non-transitory storage device comprising computer-executable instructions which when executed on one or more processors, configure the one or more processors to carry out any one of the aforementioned methods.
In the succeeding sections of the disclosure, specific embodiments of the disclosure will be described, by way of non-limiting example only, with reference to the accompanying figures, in which:
In the following description of illustrative embodiments, like numbered reference numerals appearing in different figures will be used to refer to the same features.
Different embodiments of the present disclosure provide different solutions enabling one or more battery cells comprised within a battery system comprising a plurality of cells, to be distinguished from other battery cells within the battery system. Once individual cells are distinguishable from adjacent cells within the battery system, then the individual positions of the cells may be determined.
As used herein, by position of a battery cell is intended the location of the battery cell relative to another object. For example, in most embodiments the position of a battery cell is defined with respect to other battery cells comprised within a battery system. In other words, by position of the battery cell within the battery system is intended the relative position of the battery cell within the battery system.
Notwithstanding the above, in certain embodiments the location of a battery cell may be determined. By location of the battery cell is intended the geographical position.
For non-limiting illustrative purposes, in the succeeding embodiments the electrical stimulus relates to a negative stimulus, and more particularly comprises an electrical load configured to draw current from a connected battery cell. However, it is to be appreciated that any electrical stimulus may be used which causes a change in an electrical characteristic of the connected battery cell, such as a change in voltage.
Returning to
In accordance with some embodiments, method 200 may be repeated for all battery cells comprised within the battery system, thereby enabling a position to be associated with each cell within the battery system, and more specifically, enabling a position to be mapped to each unique ID of each battery cell. During manufacture of the battery system, and during manufacture of the battery cells, a unique ID is associated to each cell. However, unless the position of each cell is mapped during assembly of the battery system, the position of each cell, as identified by its associated unique ID, is unknown. Thus, whilst the unique ID of each battery cell comprised within the battery system may be known, the positions of the cells are unknown.
In accordance with certain embodiments, the determined position information may be stored in a non-transitory storage device. For example, the battery cell position information may be stored in a database within a memory. The battery cell position information may be used to complement cell analytics monitoring system, such as a fault detection system, although this is but one non-limiting example of how the battery cell position information, obtained using the herein disclosed methods and apparatus, may be used. The present disclosure does not limit how the determined battery cell position information may be used.
As used herein, the term unique ID is to be understood as any identifier which uniquely identifies a cell within a battery system. Accordingly, the unique IDs associated with the different battery cells comprised within a battery system differ from each other to uniquely identify the associated battery cell. It suffices for the purposes of the present disclosure that the unique ID is unique with respect to the unique IDs associated with the other battery cells comprised in a battery system, to avoid any two or more battery cells comprised within a battery system sharing the same ID. In accordance with embodiments of the disclosure, the unique ID may be comprised of a string comprising one or more characters that uniquely identify the associated battery cell. For example, the unique ID may comprise any one or more of: a number, an alphanumeric string, a sequence of numerals, a string of letters, or a sequence of visual indicia.
Each battery cell 310 comprises an electrical device 315. Electrical device 315 may comprise transmitter 320 and receiver 325, configured to enable the associated battery cell to communicate wirelessly with controller 350, which itself comprises a transmitter 365 and receiver 375. In the embodiment of
In accordance with some embodiments, electrical device 315 may comprise an Application-Specific Integrated Circuit (ASIC) chip. The ASIC chip may be configured for one or more specific tasks, including monitoring one or more physical characteristics of battery cell 310 it is connected to. For example, the ASIC chip may be configured to monitor any one or more of: pressure, current, or voltage within battery cell 310. The ASIC chip may be configured to carry out any desired application. For the purposes of the present disclosure, it is immaterial what the desired application is.
In accordance with some embodiments, the unique ID associated with each battery cell 310 may be predetermined. For example, during manufacture or assembly of battery system 305. Controller 350 may be provided with access to the unique ID associated with each battery cell 310, and use the unique IDs to selectively instruct a specific battery cell to activate its associated electrical load 330.
Measurement device 340 may comprise a voltage measurement device configured to measure a voltage across a specific battery cell 310 it is connected to. Measurement device 340 communicates measurement data, for example voltage measurement data, with processor 360 via shared communication channel 345. Similarly, controller 350 may be configured to communicate with processor 360 via shared communication channel 355. Shared communication channels 345 and 355 may comprise wired or wireless communication channels.
It is to be appreciated that the functionality of transmitters 320 and receivers 325 comprised on each battery cell 310 may, in some embodiments, be replaced with transceivers configured to receive and to transmit wireless communication signals. Similarly, the functionality of transmitter 365 and receiver 375 of controller 350 may be replaced with a transceiver. In some embodiments, controller 350 may be provided with wired communication channels to communicate with each battery cell 310.
As used herein, wireless communications and communication channels may relate to radio-frequency (RF) communication protocols and channels, including Near-Field Communication (NFC), and Bluetooth® communication protocols, or any other wireless communication standard.
In accordance with some embodiments, measurement device 340 may be configured to vary its position relative to battery system 305, to enable it to connect to different battery cells 310. For example, measurement device 340 may be configured to vary its position relative to battery system 305 along a guide track (not shown) configured around battery system 305. The guide track may be configured on an external frame having a size and shape complementary to the shape of battery system 305. Measurement device 340 may be configured to move along the guide track to connect to different battery cells. Movement along the guide track may be automated. In certain embodiments, movement of measurement device 340 may be controlled by an external controller, which in certain embodiments may comprise controller 350. In certain embodiments, movement of measurement device 340 may be controlled by an external human operator using a controller, such as a remote control.
In some embodiments, the position of measurement device 340 relative to battery system 305 may be manually varied by a human operator of apparatus 300.
In accordance with some embodiments, the position of measurement device 340 of
In certain embodiments, measurement device 340 may be configured with a position determining device enabling measurement device 340 to determine its position relative to battery system 305. The position determining device may comprise any one or more of: a Global Positioning System (GPS), an Inertial Navigation System (INS), a linear transducer, or any other position determining device.
Processor 360 is configured to determine the position of battery cell 310 experiencing a change in voltage due to its associated electrical load device 330 being active, from position information received from measurement device 340, when connected to the battery cell 310 experiencing the voltage change. Processor 360 may be configured to obtain unique ID information of the associated battery cell experiencing the voltage change due to active electrical load device 330, from controller 350. Further details are discussed with reference to the method of
A first signal, comprising position information associated with battery cell C1, is received from measurement device 340, by processor 360, at step 410. Whilst for present purposes the first signal is described, and illustrated in
In accordance with some embodiments, the first signal may comprise first position information associated with the position of measurement device 340 relative to battery cell C1. The position of battery cell C1 may be determined from the first position information of measurement device 340. In accordance with some embodiments, the relative position of battery cell C1 with respect to the other adjacent cells C2 to C8 is determined. Relative position information of cell C1 may be determined from the position information of measurement device 340. Position information of measurement device 340 may be obtained from a position determining device comprised in or local to measurement device 340.
At step 420, processor 360 obtains the unique ID C1 associated with the battery cell experiencing the change in voltage. In accordance with some embodiments, the unique ID may be obtained from controller 350, which was used by controller 350 to instruct battery cell C1 to activate its associated electrical load device 330. For example, controller 350 may maintain a log or record of which battery cell was instructed, and this information may be obtained by processor 360 to determine the unique ID of battery cell C1 experiencing the change in voltage. In certain embodiments, controller 350 may send the unique ID of battery cell C1 to processor 360. This may be done once controller 350 has instructed a specific battery cell, in this example battery cell C1, to activate its associated electrical load.
The sequence of steps 410 and 420 is shown for illustrative purposes only, in
The position of battery cell C1 may be determined from the received position information associated with measurement device 340, at step 430. As mentioned previously, this may comprise inferring a relative position of cell C1 within battery system 305, with respect to the other cells 310 within battery system 305, on the basis of position information associated with the position of measurement device 340 connected to cell C1. For example, in relation to
The determined position information of cell C1 may subsequently be associated with the obtained unique ID, at step 440, by processor 360. At this stage, the position of cell C1 within battery system 305 is known. This information may, in some embodiments, be stored for later use by, for example, a fault monitoring system, and/or a BMS (not shown). In some embodiments, the position information, once determined, may be stored local to the battery cell, for example, within electronic device 315.
At step 450 it is determined if any other battery cells 310 within battery system 305 require locating. This may be achieved with reference to the list of known unique IDs available to controller 350. Method 400 is ended if no further battery cells 310 require locating. Otherwise, controller 350 instructs another battery cell 310 to activate its electrical load device, and measurement device 340 is repositioned and connected to another battery cell 310 comprised within battery system 305. A voltage measurement is taken, and if no voltage drop is measured, measurement device 340 is repositioned and connected to another battery cell. This process is repeated iteratively, at step 460, until measurement device 340 measures a voltage drop across the battery cell it is connected to. This is indicative that measurement device 340 is connected to battery cell 310 requiring locating, and which is experiencing the change in voltage due to its associated electrical load device 330 being active and drawing current from it. Steps 410 through 450 are repeated, until the positions of all required battery cells comprised in battery system 305 have been determined.
In accordance with some embodiments, apparatus 300 may comprise a plurality of measurement devices, each connected to and positioned relative to a different one of the plurality of battery cells 310. Such embodiments may function in a similar way as described in relation to
In accordance with some embodiments, and as illustrated in
For non-limiting illustrative purposes, in
A second signal associated with battery cell C1 experiencing the change in voltage, is received from cell C1 at processor 360 via controller 350, at step 620. In some embodiments, the second signal may be received directly by processor 360 from cell C1, where processor 360 is configured with a wireless receiver, or is provided with a wired communication channel to cell C1.
In common with method 400 of
The position of battery cell C1 is determined by processor 360, based on the position information comprised in the received first signal—in other words, based on the position information associated with external electrical load device 540 drawing current from cell C1—at step 630. For example, in
It is to be appreciated, that in common with preceding embodiments, the position of electrical load device 540 may be defined with respect to a known cell position obtained from a known schematic of battery system 505.
At step 650 it is determined by processor 650 if any additional battery cells 310 require locating. If one or more further battery cells 310 require locating, then external electrical load 540 is relocated to a new position relative to a different battery cell 310 comprised within battery system 505 requiring locating, and current is drawn from the new battery cell external electrical load 540 is connected to, at step 660. Method steps 610 through 650 are repeated for the new battery cell external electrical load device 540 is connected to, until all required battery cells 310 have been located.
In some embodiments, apparatus 500 may comprise a plurality of external electrical load devices (not shown), each positioned relative to a different one of battery cells 310, and each configured to draw current from a different one of the cells 310. In such embodiments, relocating external electrical load device 540 may be unnecessary. The position of one or more battery cells may be determined in the same manner as described in relation to
Alternatively, the plurality of external electrical load devices may activate at different times in a random sequence or in a predefined sequence, such that only one external electrical load draws current from its associated battery cell at any one time, and consequently each battery cell experiences a change in voltage at a different time. In such embodiments, first and second signals associated with a particular battery cell experiencing a change in voltage are received at different times, at processor 360.
In accordance with embodiments of the present disclosure, electrical load device 330 of
In some embodiments, the electrical load device may be an energy dissipative passive device such as a resistor, or an active device such as a transistor.
In some embodiments the electrical load device may be an energy transfer device such as a DC to AC or DC to DC converter, configured to discharge the battery cell.
It is to be appreciated that the voltage change caused by the electrical load device may correspond to an observed pulse change in voltage. For example, the voltage change may be observed as a temporary change in voltage, in which the measured voltage value diverges from a base voltage value for only a transient period of time.
In some embodiments, the electrical load device may be configured to provide a pulsed stimulus. For example, the electrical load may be configured to draw current from the battery cell in short temporary bursts, thereby provoking a series of measurable voltage measurement pulses.
In accordance with further embodiments, both measurement device 340 and electrical load device 330 may be remotely located from battery system 305. In such embodiments a different remotely located electrical load device may be operatively coupled to each battery cell 310. Each remotely located electrical load forms an electrical circuit with the battery cell it is operatively coupled to, and may be activated by controller 350 instructing the associated battery cell, as described in relation to previous embodiments. Measurement device 340 measures a voltage change caused by the activated electrical load. Processor 360 determines the position of the battery cell experiencing the voltage change, in a similar manner as described in relation to previous embodiments.
In some embodiments comprising both remotely located measurement devices and remotely located electrical load devices, controller 350 may instruct a specific remotely located electrical load to activate causing a change in voltage in the connected battery cell. The battery cell experiencing the change in voltage may transmit its unique ID to controller 350 and/or processor 360. In such embodiments, it is not necessary for controller 350 to have access to the unique IDs of the plurality of battery cells 310. Instead, each battery cell may comprise its associated unique ID in local storage, for example in a storage of electronic device 315.
In some embodiments, electrical load device may be replaced with a positive stimulus device. For example, electrical load device may be replaced with a charger, configured to charge the battery cell it is operatively connected to. Electrical load device 540 may be replaced with a charging circuit. The herein disclosed methods for determining the position of a battery cell may be implemented using either a positive or a negative electrical stimulus. Irrespective of whether a positive or a negative electrical stimulus is used, the methods for determining battery cell position do not fundamentally change.
In accordance with some embodiments of the disclosure, battery cell position is determined on the basis of a battery cell activation sequence and a predefined assembly sequence. During assembly of a battery system, individual battery cells are assembled, and incorporated within the battery system. This includes placing each battery cell within the battery system at specific locations, in accordance with a predefined assembly sequence. At some stage during the assembly process, each battery cell is activated to ensure that it is functioning correctly within the battery system. This may occur as each battery cell is placed within the battery system, or once all battery cells have been placed within the battery system. A record of where each battery cell is located within the battery system, as identified by its unique ID, is often not maintained. In such cases, and in accordance with some embodiments, the position of each battery cell within the battery system may be determined based on the activation sequence in combination with the predefined assembly sequence. Further details of such embodiments are set out below.
Each battery cell 710 comprises processing device 715. Processing device 715 may be a microprocessor. In some embodiments, processing device 715 may be an Application-specific Integrated Circuit (ASIC). Each cell 710 may comprise an RF transmitter 320 configured to transmit RF signals to RF receiver 740. Battery cells 710 may be configured to transmit an activation signal to RF receiver 740 when they are first activated during assembly. In some embodiments, the activation signal may be transmitted as processing device 715 comprised on each cell 710 is first activated during assembly.
In accordance with some embodiments, RF receiver 740 may comprise clock 750 configured to measure a time coordinate associated with each received activation signal. For illustrative purposes, in
Once cell C1 has been placed within battery system 705, its associated processing device 715 activates, and activation signal t1 is sent to RF receiver 740. Activation signal t1 is received by RF receiver 740, at step 810. Activation signal t1 comprises information enabling the unique ID of cell C1 to be determined. In some embodiments, and as described in relation to preceding embodiments, activation signal t1 may comprise the unique ID of cell C1. A time coordinate is associated with the received activation signal, by processor 360, at step 820. The time coordinate may relate to a time of receipt of activation signal t1 by RF receiver 740, measured by clock 750. RF receiver 740 and processor 360 share communication channel 760, enabling signals and measured time coordinates to be provided to processor 360. It is to be appreciated that for non-limiting illustrative purposes only, RF receiver 740 and processor 360 are illustrated as separate devices, but in some embodiments may be comprised in the same device, and/or their functionality may be provided by the same physical device.
If any additional battery cells are placed into battery system 705 and activated at step 830, then steps 810 and 820 are repeated for each received activation signal associated with a newly activated battery cell. For example, as cell C2 is placed within battery system 705, activation signal t2 is received and steps 810 and 820 are repeated. The same steps are repeated with activation signal t3, and so forth.
Remaining method steps 840 and 850 may be performed by processor 360 once at least two activation signals associated with two different activated battery cells have been received. However, in certain embodiments the remaining method steps 840 and 850 are performed once all battery cells comprised in battery system 705 have been activated, and for present purposes the remaining steps of method 800 will be described in relation to such an embodiment.
Once cells C1 through C8, and more specifically their associated processing devices 715 have been activated, and a time coordinate associated with a time of receipt of each received activation signal has been associated to each received activation signal, an activation sequence defining the order in which processing devices 715 have been activated, is determined by processor 360, at step 840. The order in which the different processing devices 715 were activated is synonymous with the order in which battery cells 710 were assembled within battery system 705. The activation sequence identifies the order in which the plurality of battery cells 710, as identified by their respective unique IDs, were assembled within battery system 705.
The position of each battery cell 710 within battery system 705 is determined, on the basis of the activation sequence and the known predefined assembly sequence, at step 850. The predefined assembly sequence defines a physical order in which the plurality of battery cells 710 within battery system 705 are to be assembled. In other words, the assembly sequence defines a positional sequence in which the plurality of battery cells 710 are to be installed within battery system 710. As mentioned previously, this may comprise defining the sequence in which battery cell positions P1 to P8 are occupied by battery cells 710 during battery system assembly. The predefined assembly sequence may be comprised within the assembly procedure for battery system 705.
An example of a predefined assembly sequence, with reference to
One way in which the activation sequence may be determined is to arrange each received activation signal in order of the time of receipt. In other words, by determining a chronological order of receipt of the activation signals. The chronological order of receipt of the activation signals is related to the predefined assembly sequence, since the assembly sequence defines the positional order in which battery cells 710 are installed within battery system 705, and consequently the order in which the cells 710 are activated. The unique ID associated with each cell 710 is provided by the activation sequence, whilst the assembly sequence provides the position information. Associating the activation sequence with the assembly sequence results in a specific position being associated with the unique ID of each battery cell 710. It is to be appreciated, that cell activation may relate to the process whereby processing device 715 is fixated to a battery cell 710. Similarly, in some embodiments, cell activation may relate to the process whereby a battery cell 710 comprising processing device 715 is physically inserted and connected to battery system 705.
In some embodiments each processing device 715 may comprise a clock 770 configured to begin measuring time when the associated battery cell 710 is activated. The activation signal transmitted to RF receiver 740 comprises a time coordinate associated with the time of transmission as measured by clock 770 local to cell 710. The time of transmission as measured by clock 770 is indicative of the passage of time from when the associated battery cell and/or processing device 715 was activated, and transmission of the activation signal. Since each battery cell 710, and each processing device 715 is activated at a different time, there will be an inherent time difference between clocks 770 associated with the time delay between the activation of different battery cells 710. One way of mitigating for this time delay present in clocks 770, is for cells 710 to transmit their activation signals at the same time once all battery cells have been activated. This ensures that the time difference between the time coordinates associated with any two or more different received activation signals is directly proportional to the time lapse between activation of the different cells 710 and/or processing devices 715.
Once each activation signal has been received, processor 360 determines a time difference between the time coordinates associated with the different received activation signals, at step 920. The determined time differences together with the unique IDs may be used to determine the activation sequence from the received activation signals, at step 930. For example, the greatest determined time difference will be determined when comparing the time coordinates of the first activated cell and/or processing device 715, and the last activated cell and/or processing device 715. Similarly, the time difference between two sequentially activated cells and/or processing devices will be smallest. Thus, the activation sequence may be determined by analysing the determined time differences between the time coordinates comprised in the received activation signals. The chronological order in which the plurality of battery cells 710 and/or processing devices 715 were activated is given by the determined activation sequence.
The determined activation sequence may then be associated with the predefined assembly sequence by processor 360, at step 940. The position of each cell 710 within battery system 705 is now known.
In accordance with some embodiments, the predefined assembly sequence may be stored in a memory (not shown) accessible to processor 360. The memory may be local to, or remotely located from, processor 360.
In accordance with some embodiments, rather than receiving a plurality of different activation signals from the plurality of battery cells 710, the plurality of activation signals may be concatenated into a single carrier signal prior to transmission to RF receiver 740. For example, battery system 705 may comprise a modulator configured to concatenate the individual activation signals onto a single carrier signal. In such embodiments, each battery cell 710 may not comprise transmitter 320. Instead, battery cells 710 may be provided with a communication channel connecting each battery cell 710 to a modulator. Once each activation signal has been concatenated and modulated onto a carrier signal, the carrier signal may be wirelessly transmitted to RF receiver 740, via a transmitter operatively coupled to the modulator. In turn, RF receiver 740 may comprise a demodulator configured to demodulate and extract the individual activation signals from the received carrier signal. The associated time coordinates and unique IDs may then be recovered, and processor 360 may proceed to determine battery cell position in a similar manner as described in relation to method 900 of
In accordance with some embodiments, activation signals may relate to short-range wireless signals. For example, they may comprise short-range signals in accordance with any one of near-field communication (NFC) communication protocols, or Bluetooth® communication protocols.
Number | Date | Country | Kind |
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21167518.6 | Apr 2021 | EP | regional |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2022/058909 | 4/4/2022 | WO |