Communication system for monitoring battery system

Abstract

The present disclosure relates to a communication system for monitoring a battery system. The communication system is a multi-level system having different time division multiple access (TDMA) at respective levels.

Description

Background Technology

[0001] Battery systems comprising multiple battery cells are used in a wide range of modern electrical applications. For example, they are used to power electric vehicles, industrial power applications, transportation, and commercial applications such as modern electronic devices. Given the relatively high power requirements of such applications, battery systems typically comprise multiple battery cells coupled together to achieve the required power output. Battery cells may be coupled together to form a battery pack, and a battery system may include one or more battery packs.

[0002] Typically, the battery system is connected to a battery management system (BMS), which is configured to ensure the battery system operates within its safe operating area. The safe operating area is defined as the voltage, current, and environmental conditions under which the battery system is expected to operate without self-damage. For further details, interested readers can visit the following Wikipedia page: https: / / en.wikipedia.org / wiki / Battery_management_system.

[0003] In some known applications, the performance characteristics of battery cells within a battery system can be monitored to identify potential malfunctions in the cells before a catastrophic failure occurs. Such measurements are performed using a device called a Cell Monitoring Device (CMD). The CMD provides cell-level measurements, allowing individual measurements to be taken of each cell and the information obtained is specific to that cell. Additional measurements can be obtained using auxiliary devices, which may acquire measurements from groupings of cells or at the battery pack level. Measurements acquired by the CMD and / or auxiliary devices are typically transmitted to the central controller via the battery management system. Summary of the Invention

[0004] For proper maintenance and adjustment of battery systems, measurements need to be obtained with high accuracy. However, as battery systems scale to larger dimensions, latency issues can arise due to the greater distances that measurements and / or communications travel throughout the battery management system. Therefore, a system is needed to improve communication within the battery management system. The example embodiment presented herein employs a multi-level communication system using a Time Division Multiple Access (TDMA) protocol.

[0005] The example embodiments presented herein include a communication system for monitoring a battery system. The communication system includes a single Time Division Multiple Access (TDMA) protocol operating across the communication system. The communication system further includes a plurality of electronic devices located at a first level of the communication system, wherein each electronic device is configured to obtain measurements relating to at least one corresponding battery cell of the battery system, and wherein the plurality of electronic devices are arranged in at least two subgroups of electronic devices. It should be understood that the electronic devices may take the form of a CMD, an auxiliary device, or any other component capable of performing battery cell or battery-related measurements or controlling battery cell or battery-related functionality. It should further be understood that the term 'at least one corresponding battery cell' should include an individual battery cell or a plurality of battery cells in a battery pack.

[0006] The communication system further includes at least two radio manager units located at a second level of the communication system, wherein each subgroup of electronic devices is scheduled via a first TDMA and communicates with a corresponding radio manager unit through a first communication medium. The communication system further includes at least one radio pointer unit located at a third level of the communication system, wherein each radio manager unit and at least one radio pointer unit are scheduled via a second TDMA and communicate through a second communication medium.

[0007] At least one radio pointer unit is configured to determine a second TDMA schedule, and each radio manager unit is configured to determine a corresponding first TDMA schedule, wherein the first TDMA schedule and the corresponding second TDMA schedule define the timing for the synchronous transmission of measurement-based reporting and instruction messages throughout the communication system.

[0008] Example embodiments also relate to a method in a communication system for monitoring a battery system, wherein the communication system operates across a single Time Division Multiple Access (TDMA) system protocol. The method includes: determining a first TDMA schedule for communication between a plurality of electronic devices and at least two radio manager units via a first communication medium, wherein the plurality of electronic devices are located at a first level of the communication system and are arranged in at least two subgroups of electronic devices. The at least two radio manager units are located at a second level of the communication medium.

[0009] The method further includes: determining a second TDMA schedule for communication between at least two radio manager units and at least one radio pointer unit via a second communication medium, wherein the at least one radio pointer unit is located at a third level of the communication system. The method also includes: obtaining measurements regarding at least one corresponding battery cell of the battery system via a plurality of electronic devices. The method additionally includes: transmitting the obtained measurements to at least two corresponding radio manager units via a first TDMA schedule and through a first communication medium. The method further includes: further transmitting the obtained measurements to at least one radio pointer unit via a second TDMA schedule and through a second communication medium. At least one radio pointer unit is configured to determine the second TDMA schedule, and each radio manager unit is configured to determine a corresponding first TDMA schedule, wherein the first TDMA schedule and the corresponding second TDMA schedule define the timing for synchronously transmitting measurement-based reporting and instruction messages throughout the communication system.

[0010] Example embodiments also relate to a computer-readable medium storing instructions that, when executed by a processor of a communication system for a battery system, cause the communication system to perform the methods described herein. Attached Figure Description

[0011] The foregoing will be described in more detail below with reference to the exemplary embodiments shown in the accompanying drawings, in which reference numerals refer to the same parts in different views. The drawings are not necessarily to scale, but rather focus on illustrating exemplary embodiments.

[0012] Figure 1 This is a diagram of the measurement, monitoring, and control components within a battery monitoring system;

[0013] Figures 2 to 4 This is an illustrative example of a communication system within a battery monitoring system;

[0014] Figure 5 These are illustrations of a communication system within a battery monitoring system based on some example embodiments of the exemplary embodiments presented herein;

[0015] Figure 6 This is a schematic diagram of a switching mechanism associated with a radio manager unit according to some example embodiments of the exemplary embodiments presented herein;

[0016] Figure 7 and Figure 8 These are some example embodiments based on the exemplary embodiments presented herein. Figure 5 An illustrative example of a message passing sequence diagram for a communication system; and

[0017] Figure 9These are illustrative examples of multi-layer communication systems within a battery monitoring system, based on some of the exemplary embodiments presented herein. Detailed Implementation

[0018] Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. The following description refers to the accompanying drawings, in which, unless otherwise stated, the same numerals in different figures represent the same or similar elements. The embodiments set forth in the following description of the exemplary embodiments do not represent all embodiments consistent with the invention. Rather, they are merely examples of apparatuses and methods consistent with aspects of the invention recounted in the appended claims.

[0019] This document describes a component for providing a communication system for a battery monitoring system. The battery monitoring system may be included within an electric vehicle and / or battery storage component. For background information, an overview of the battery monitoring system will be provided. A battery system typically comprises multiple battery cells connected in some configuration to provide the required battery system voltage and capacity, as well as additional components required for the safe operation of the battery cells and the transfer of energy to / from the battery cells. The battery cell is the basic unit of any battery system. The defining characteristic of a battery cell is its electrochemical properties. For a given battery cell chemistry, there are minimum, typical, and maximum voltages, which are determined by the electrochemical properties of the battery cell, not by the system configuration. Voltage cannot be changed except by altering the electrochemical state of the battery cell. Battery cells may be connected in parallel to increase the overall capacity, but from a battery cell monitoring perspective, these parallel battery cells can simply be considered as larger individual battery cells, as they still possess the same voltage characteristics determined by their electrochemical properties.

[0020] Battery cells can also be connected in series. A series stack of battery cells has a voltage primarily determined by the stack configuration. The stack voltage is the sum of the voltages of the individual battery cells. The stack voltage can be changed by adding or removing battery cells without altering the electrochemical state of the cells. Typically, the stack of battery cells undergoes charging and discharging, causing their electrochemical state to change. Each battery cell must be monitored to ensure that each cell is within its safe operating area. This is precisely the function of a Cell Monitoring Device (CMD). A CMD provides cell-level measurements, allowing for individual measurements of each battery cell and providing information specific to that individual cell.

[0021] A battery pack consists of multiple battery cells connected in series. The battery pack provides the complete battery system voltage. Multiple battery packs can be connected in parallel to increase the battery system capacity, but not in series. Battery cells can be divided into modules. The defining characteristic of a module is its physical configuration, such as the number of battery cells and their interconnections. A module can include any number of battery cells. A module may include two or more battery cells, or it may include the entire battery pack. If the battery system contains only a single battery pack, then a module can contain the entire battery system.

[0022] However, more commonly, battery packs are configured as multiple modules, each consisting of multiple battery cells connected in series. These modules are then connected in series, parallel, or a combination of series and parallel connections. Modules connected in parallel with the same voltage as the battery system can be considered a battery pack. Modules have defined dimensions and shapes and are typically encapsulated in some type of housing.

[0023] Module configuration is driven by the physical requirements of the battery pack. Typically, modules are configured to have a sufficiently low voltage to allow for disposal without the risk of electric shock. Typically, modules are configured to match the number of battery cells in a battery cell monitoring device. A very common example is a twelve-cell monitoring device. The module then consists of twelve battery cells and connections to the battery cell monitoring device. In many battery packs, the CMD's properties define the module configuration, and the battery pack is then constructed from multiple such modules.

[0024] While a CMD can be used to obtain cell-level measurements of a battery system, auxiliary devices can be used to obtain measurements associated with multiple cells within a module, battery pack, and / or battery system. Auxiliary devices provide module-level, battery pack-level, and / or system-level measurements and can be flexibly placed anywhere within the battery system. The term 'electronic device' is used herein as a device that provides measurements in a battery monitoring system. It should be understood that an electronic device can be a CMD, an auxiliary device, or any other device located within the battery system capable of obtaining measurements or providing control.

[0025] Figure 1 An example battery system is shown, which includes auxiliary device 115 and various CMDs 107. Figure 1 The battery system 116 includes a single battery pack 117 having eight battery modules 101. Each battery module 101 has twelve battery cells 105. Each battery cell 105 is monitored by a corresponding CMD 107, which provides cell-level measurements. Each CMD 107 is configured to communicate with a central controller or BMS via a near-field communication bus 109. To enable such communication, each CMD includes a corresponding near-field antenna 111. It should be understood that, although Figure 1 The example illustrates near-field radio communication, but other forms of communication systems can be employed. For example, Figure 1 The battery system can have communication channels in the form of far-field radio, optical bus and electrical bus, such as Controller Area Network (CAN), Ethernet, Isolated Serial Peripheral Interface (isoSPI), Local Interconnect Network (LIN), Flexray, etc.

[0026] According to some example embodiments in the example examples, auxiliary equipment may be placed on or within the battery system to obtain module-level or battery pack-level measurements. Figure 1 In the example provided, auxiliary device A is located within the housing of each battery module 101. This placement allows the auxiliary device to obtain module-level measurements of the battery system. It should be understood that the auxiliary device can be placed near multiple modules, such that a single auxiliary device can obtain module-level measurements of multiple modules. In this example embodiment, the auxiliary device may be located, for example, between two adjacent modules.

[0027] In the Figure 1 In the provided examples, auxiliary device A is also positioned in a location that allows for battery pack-level measurements. Specifically, auxiliary devices A 120, 121, and 122 provide examples of auxiliary devices with a battery pack voltage measurement sensor, a battery system isolation resistance measurement sensor, and a battery pack current measurement sensor, respectively. Another example of placement for auxiliary devices used to obtain battery pack-level measurements is provided in 123, where the auxiliary device is placed near the battery pack switch (often referred to as a contactor) and its associated drive and sensing circuitry. Auxiliary device A 124 can be configured to measure the output voltage of the battery pack. As another example, auxiliary device A can be placed near the main power connection (traction connector) 125 to the battery system. The power connection includes a safety interlock switch that indicates the presence of the mating connector. Auxiliary device A on 125 is able to report the status of this safety interlock switch.

[0028] The enlarged view 115 of auxiliary device A provides examples of features that can be included in the device. Figure 1 In the example provided, auxiliary device A may include temperature and voltage sensors. It should be understood that auxiliary devices may include any number or type of sensors for monitoring the battery system. Examples of such sensors may be temperature, voltage, current, pressure, shock, gas, grounding leakage, security / tamper detection, interlock status, fluid flow rate, gas flow rate, actuator position, fan / motor speed detector, and / or other environmental sensors. Auxiliary device 115 may further include a radio frequency antenna 113 for communicating with the central controller 118 or BMS via near-field communication bus 109 in the same manner and using the same protocol as the individual CMD.

[0029] Battery monitoring systems (such as) Figure 1 The system shown in the example requires a communication system to send messages and commands to various components of the monitoring system. Various requirements exist for the battery cell monitoring system. For example, the monitoring system should be able to measure the voltage of each battery cell with high accuracy and optionally measure the temperature. Furthermore, ideally, all battery cells should be measured simultaneously to facilitate comparison of performance between cells. Measurements should also be performed cautiously to ensure reliable data connections between battery cells and maintain voltage isolation. Additionally, the system must be easy to manufacture and maintain. The system should also be scalable, and for larger battery systems, latency issues should be minimized.

[0030] Figure 2 This is an illustrative example of a communication system 200 associated with a battery monitoring system known in the art. Figure 2 A host device 201 is depicted, representing an application of a battery system used in, for example, a vehicle or stationary energy storage device. The host device 201 directs a controller or battery management system (BMS) master device 203. The controller 203 communicates with a series of electronic devices (ED1-EDx) that measure any number of lithium-ion battery cells in a battery pack or a grouping of lithium-ion battery cells within a battery pack. The electronic devices may also provide control elements such as relays or contactors, or electronically triggered fuses, or thermal controls. The electronic devices can be CMDs, auxiliary devices, or any other node in a battery monitoring system capable of measuring one or more battery cells, modules, or battery packs. Typical electronic devices measure 12 battery cells, and multiple electronic devices measure all battery cells in a battery pack, such as 96 or 192 battery cells. Therefore, there can be 8 or 16 electronic devices in a system. The electronic devices are arranged in a daisy-chain configuration, where instructions from the controller 203 to the electronic devices are passed down the daisy chain, and measured data is passed back up the daisy chain from the electronic devices. The daisy chain is typically implemented using protocols such as the Isolated Serial Peripheral Interface (isoSPI).

[0031] System 200 has several drawbacks. Latency (the time it takes for a message to travel from the controller to the electronic device or back) is different for each electronic device. Therefore, synchronizing all electronic devices so that they perform measurements at exactly the same time becomes difficult.

[0032] Figure 3a illustrates a communication system 300a employing an alternative approach. Here, daisy-chain communication is replaced by a radio frequency channel, such as the 433MHz, 868MHz, 915MHz, 2.4GHz, or 5.7GHz short-range device (SRD) or industrial-scientific-medical (ISM) band. This channel is configured with antennas at the controller (now called the radio manager or RM 303a) and at each of the electronic devices (ED1-ED1x) to enable communication between the electronic devices and the host 301a. This is sometimes referred to as a wireless BMS because communication is conducted via a far-field wireless link.

[0033] and Figure 2 Compared to the daisy-chain method shown in the diagram, communication system 300a has several advantages. For example, the communication (i.e., single-hop) delay between any pair of antennas is constant. Furthermore, the number of cables and connectors is reduced. However, maintaining single-hop communication within the boundaries of the battery pack is very difficult. Typically, battery cells cannot directly 'see' the RM and must relay messages via intermediate battery cells. This is a mesh network solution. These are also undesirable because they increase latency and make it unpredictable. Additionally, the timing of all measurements for the synchronizing electronics remains problematic.

[0034] Figure 3b illustrates a variant of the wireless BMS. Here, the far-field method is replaced by a near-field multipoint method. Each electronic device is weakly coupled to the bus antenna. This keeps the latency low and predictable. Furthermore, the latency is the same for all RM / electronic device pairs using this method. The signal is propagated along the bus antenna, thus eliminating the need for multi-hop or mesh networks.

[0035] The bus antenna in Figure 3b is typically a pair of wires configured as a transmission line. Bus antennas can be several meters long. A typical automotive battery pack might require a 5-meter-long bus antenna. However, some applications require much longer bus antennas, such as 20 meters or more. The longer the bus antenna, the greater the signal power loss along it.

[0036] The losses present in the bus antenna refer to the length of the line where the electronics located at the ends of the bus antenna may not receive sufficient power. For example, the transmitter in the RM may lose -20 dBm. There may be a 30 dB attenuation across the near-field gap to minimize the load on the electronics on the bus antenna. Other losses within the system can total up to 10 dB. Therefore, the total loss of the system can be (-20-30-10) = -60 dBm. The electronics receiver has a sensitivity of -80 dBm (which is the minimum received signal strength). This leaves room for an additional 20 dB of loss. The bus antenna can have a loss of 2 dB per meter. Therefore, the maximum bus antenna length in this example is 20 dB / 2 dB = 10 meters.

[0037] Figure 4 A variant of the communication system 400, as shown in Figure 3b, is illustrated, in which the total length of the bus antennas can be greater than the length indicated by the simple calculations described above. The splitter 405a / combiner 405b assembly splits the RF signal from the controller 403 between the two bus antennas. The power of each bus antenna is reduced by 3 dB (divided by two). However, as long as the bus antennas only need to cover half of the battery cell, only half the length of the bus antennas is required. The second bus antenna experiences the same power as the first bus antenna.

[0038] The splitter 405a / combiner 405b does not need to be located at the controller, and in large systems, the controller 403 and the splitter 405a / combiner 405b can be located at a distance from the electronic equipment. The electronic equipment can be grouped into modules or racks, and the entire system can be the size of a shipping container or larger. The main unit 401 can also be located at a distance.

[0039] Of course, a solution could be to have multiple electronic devices, all communicating with the host. However, this raises the same issues previously associated with measurement synchronization. For proper maintenance of the battery monitoring system, it is useful for all electronic devices to perform measurements simultaneously, for example, within microseconds.

[0040] Therefore, the example embodiments proposed herein provide a communication system for use with battery monitoring, wherein communication losses due to system size are minimized. Furthermore, the communication system proposed herein also provides a fixed and short communication latency, which eliminates the need for hopping or identical latency hopping across all electronic devices. Additionally, the example embodiments proposed herein provide synchronization of measurements across all electronic devices in the system within microsecond timeframes. The example embodiments proposed herein further provide network formation at a single node (e.g., a controller or radio manager) to achieve reliable and repeatable network formation time and fault identification. Isolation maintenance between subsystems and high voltages (e.g., 500 VDC to 1500 VDC) is also provided, as well as low-power milliamp (mA) and microamp (µA) sleep current per node.

[0041] Figure 5 A battery monitoring communication system according to an example embodiment presented herein is illustrated. The communication system 500 includes a three-tier architecture. The first tier includes various electronic device groups. Figure 5 The example shows three distinct groups, each containing four electronic devices (ED1:1-ED3:4). The second level includes multiple radio manager (RM) units 505a-505c. Distinct RM units are associated with corresponding groups of electronic devices. Figure 5In the example shown, RM unit 505a is associated with a first group having electronic devices ED1:1-ED1:4, RM unit 505b is associated with a second group having electronic devices ED2:1-ED2:4, and RM unit 505c is associated with a third group having electronic devices ED3:1-ED3:4. Radio pointing unit 503 is located at the third level of the communication system and has direct communication with host 501.

[0042] It should be noted that Figures 2 to 4 The communication system comprises a two-tier architecture, with a controller or radio manager located between the host and the electronic devices. Therefore, the example embodiment presented herein increases the number of tiers from two to three or more. Multiple electronic devices are grouped into branches, with each branch connected to an RM unit. Each group of electronic devices on the first tier of the architecture is synchronized with its associated RM unit on the second tier. Each RM unit on the second tier of the architecture is, in turn, synchronized with a radio pointer 503 on the third tier. The communication protocol is uniform across all tiers. RM units 505a-505c can switch from communicating with the tier above them to communicating with the tier below them. The time required to switch from one tier to another is significantly less than the time required to transmit data packets.

[0043] The highest level has at least one node. This is the Radio Pointer (RD) unit 503. At the start of a frame, the RD unit 503 broadcasts RM units 505a-505c to the second level. The second level times the data packets relative to the first level and follows the instructions contained in the RD unit broadcast. The RM units 505a-505b broadcast to all corresponding electronic devices on the third level.

[0044] During operation, Figure 5 All components will operate using the same communication protocol (e.g., Time Division Multiple Access (TDMA) protocol). However, different architectural layers of System 500 will operate using different TDMA timing schedules. It should further be understood that different architectural layers of System 500 may also be included in different communication media, such as far-field radio, near-field radio, optical, electromagnetic, or any other form of communication media. RM units 505a-505c located in the intermediate or second layer have the functionality to switch between different communication media in different architectural layers. It should be understood that different layers do not necessarily include different communication media and may use the same media. Figure 5 In the example shown, the first layer of the communication architecture includes a near-field radio communication medium, and the third layer of the communication architecture includes a far-field radio communication medium.

[0045] Figure 6An example of a switching mechanism that can be included in each RM unit 505a-505c is shown. RM units 505a-505c switch between the two physical channels at a rate fast enough to maintain synchronization between the EDs. If synchronization can be maintained for up to 200ms, a TDMA scheduling frame rate much less than 200ms is required to maintain synchronization. This may require a frame rate of 10ms to 100ms.

[0046] The nature of the physical channel can vary. In embodiment a), the RD<->RM layer (communication architecture layer 3) is a far-field radio using a standard 2.4 GHz antenna. The RM<->ED layer (communication architecture layer 1) is a near-field multipoint bus antenna method.

[0047] Other communication protocols, such as Bluetooth or IEEE 802.11, also include mechanisms for synchronizing clocks across multiple nodes. However, these protocols cannot operate across more than two layers without buffering and tight synchronization loss. Mesh networks such as Bluetooth Mesh or SmartMesh also exist, operating across multiple layers or hops. However, these mesh networks are nondeterministic, with variable latency and indeterminate synchronization because the number of hops required for a message or synchronization to reach all nodes is unknown in advance. Mesh networks use a single antenna or channel for all links. While mesh networks can maintain synchronization across layers, this synchronization is difficult because the number of layers or hops is indeterminate. Specifically, mesh networks may require synchronization at a high communication cost and configuration overhead. Essentially, variable latency must be measured and compensated for. The achieved synchronization is difficult to predict (not deterministic) and is generally worse than what is practically achievable.

[0048] There are also radio systems that use multiple antennas for direction finding. These systems switch rapidly between antennas while maintaining carrier coherence (i.e., continuous phase of the carrier). The example embodiments presented herein do not require coherence; antenna switching occurs between packet transmissions, not during packet transmission. Each packet is independent and is received or transmitted from a different transceiver depending on the switching state.

[0049] The difference in the example embodiments lies in the fact that a single radio block switches between two different physical channels. Example a) is a good example where the RD<->RM layer is far-field and the RM<->ED layer is a near-field bus antenna. Example b) shows a far-field antenna for both layers, which may be ideal if the two antennas are placed in different locations, possibly on either side of a metal screen. Example c) shows a wired (coaxial or twisted-pair) RF connection from RM<->RD and a near-field bus antenna from RM<->ED. The physical nature of the radio link is not important, whether it is wired, near-field, or far-field. In each case, the modulated signal is transmitted and received by the same radio block on the RM.

[0050] It should be understood that the use of RM units 505a-505c with switching mechanisms is merely an example. A single radio component at RM units 505a-505c is not necessary; using two radio blocks without switching is also feasible. However, the circuitry would be larger and more complex. If two radio blocks are used, they will not operate simultaneously in this approach, thus wasting circuit resources without any added benefit.

[0051] According to an example embodiment, RD unit 503 is configured to determine a TDMA schedule for communication between the third and second tiers of the system architecture (i.e., between RD unit 503 and each RM unit 505a-505c). Similarly, each RM unit 505a-505c is configured to determine a TDMA schedule for each corresponding ED packet. The TDMA schedule defines the timing for measurement sampling timing, measurement reporting, and command message transmission in a synchronous manner within the communication system.

[0052] Figure 7 It shows that it can be made by Figure 5 The communication system 500 employs an example TDMA timing scheduler. Communication timing is broken down into multiple frames, each a complete instruction / synchronization / response cycle. Each frame is divided into one or more time slots. A frame consists of multiple steps. The function and order of these steps are not critical; many arrangements will be effective. Figure 5 The arrangement is provided merely as an example. It should be understood that there is an RD to RM stage that synchronizes all RM clocks, which set the timing for subsequent communications; and an RM to ED stage that synchronizes all ED clocks, communications, and measurements.

[0053] This synchronization process can occur on every frame, or less frequently if nodes remain synchronized for a longer period. Synchronization must occur frequently enough for all nodes to remain within specified timing error limits. It should be understood that intermediate layers (e.g., the RM on layer 2 in a three-layer system) can communicate both upwards to higher layers (RD on layer 3) and downwards to lower layers (ED on layer 1). It is advantageous that these communications use the same radio circuitry but operate through different media. In one example embodiment, a single radio block exists in the RD, RM, and ED. In the RM, the radio input / output switches between the two media.

[0054] In the Figure 7 In the provided example, the first time slot is a broadcast from the highest-level (level 3 in this example) RD unit 503 to all RM units 505a-505c on level 2. All RM units 505a-505c configure their antenna switches from level 3 to level 2, as follows: Figure 7 The middle time slot 1'RM switches from RM to RD as indicated. Specifically, in Figure 7 In time slot 1, RD (labeled 'RD LVL3') directs... Figure 5 All RMs (marked as 'RM1 LVL2', 'RM2 LVL2', and 'RM3 LVL2') send broadcast messages indicated by solid black lines.

[0055] The first time slot synchronizes the communication of the rest of the frame and instructs the RM and RD units on what responses they expect to see in subsequent time slots. All ED and RM units do not need to respond in a single frame; if necessary, communication can be distributed across multiple frames.

[0056] exist Figure 7 In the example, in slot 2, all RM units 505a-505c switch communication to the first architecture level (labeled 'RM switch 2 to 1 (RM to ED)') and transmit instructions to the corresponding ED. Each RM unit then broadcasts to all EDs connected to the same branch within the corresponding group. RM units 505a-505c instruct each ED which measurement (voltage, temperature, etc.) to perform and when to perform it. Multiple measurements can be directed at different times.

[0057] As guided in the current example, all EDs perform measurements in time slot 3 to collect results. Specifically, in time slot 3, the EDs perform their measurements, and all measurements are synchronized with the timing of the broadcast data packets in time slot 2, which in turn are synchronized with the timing of the RD broadcast data packets in time slot 1. In time slots 4, 5, and 6, the EDs return their measurement results to their respective RM units, one ED per time slot. It should be understood that the RM units are capable of parallel communication because they are all switched to their respective channels. In time slots 4, 5, and 6, each RM unit can operate at a different frequency to avoid interference between RM / ED channels. The RM units receive and store the results for transmission in subsequent time slots. In time slots 7, 8, and 9, the RM units switch their antennas back to the channel of RD unit 503. Each RM unit 505a-505c transmits its stored results in the time slot assigned to it in the broadcast in time slot 1. It should further be understood that the measurement and data return are decoupled in time. Measurement M will occur in frame F and may be returned in frame F, or it may be stored or placed in a buffer until the next frame. Data may not be returned until the next frame F+1 or a larger frame.

[0058] In more substantial examples, hundreds of EDs can exist on each RM branch. Numerous RM units can also exist. TDMA packets incur overhead in the form of preambles, addresses, error checks, and other non-payload data. Therefore, long packets with large payloads are more efficient. With multiple RM / ED channels, many RM / ED data transfers can occur concurrently, improving communication efficiency. By tidying up the results at RM units 505a-505c, subsequent RM / RD packets can include more data in longer payloads, further improving communication efficiency. Furthermore, the example embodiments described herein use disparate TDMA scheduling at different architectural levels to maintain deterministic protocols and synchronization across all levels.

[0059] There are many ways to construct frames. For example, a more complex TDMA timing diagram can be used. Here, RM communications to RD unit 503 and ED are interleaved to improve throughput. It also includes time slots for retries, as well as different responses from different nodes in different frames.

[0060] Figure 8 More complex examples are shown. Figure 8 Time slots 1-6 and about Figure 7 The time slots described in the text are similar. Figure 8Time slot 7 is used for retries, where previously transmitted data packets may fail to be received due to corruption and are resent to the corresponding RM unit. This requires a communication controller capable of reordering the content and timing of transmissions on a frame-by-frame basis. A data packet sent from ED1:1 to RM 505a in time slot 7 might be a failed packet from a previous frame, while a retry of ED3:3 in time slot 15 might be due to a failure in time slot 6. Similarly, retries may exist for data packets sent from RM units 505a-505c to RD unit 503. This is shown in time slots 8 and 16. By providing sufficient retry time slots, data packets can be guaranteed to pass with an arbitrarily high probability.

[0061] In some example embodiments of the example implementations, multiple frames may be combined into a superframe. If needed, communication can be made across a single superframe with all EDs. In some networks, a single frame may be sufficient for communication with all EDs; in larger networks, multiple frames may be required.

[0062] At the start of a frame, it may be little or no assumption that all RM and ED nodes are clocked in sync. While there may be residual synchronization from previous frames on all nodes, if they are not synchronized, the clocks will diverge, and the spread will increase over time. Ultimately, nodes will transmit and receive too early or too late, and measurements will be taken at highly variable times.

[0063] It should be understood that, although Figure 5 The system has a three-tier architecture, but this configuration is merely an example. According to the example embodiment, multiple RM units can be used to create communication systems with more than three tiers. Figure 9 An example of a communication system with four architectural layers is provided. Specifically, Figure 9 The system has a first level for various ED groups and a second level for a first RM unit (RM1), where an RM1 unit is associated with a corresponding ED group. Figure 9 The system further includes a third architectural layer with multiple second RM units (RM2), each RM2 unit being associated with a corresponding RM1 unit group. Finally, at the fourth architectural layer, an RD unit (RD1) is provided, and it communicates directly with all RM2 units. It should be understood that... Figure 9 The system shown is merely an example, and communication systems as described herein can include any number of architectural layers (i.e., any number of three or more layers). Such as Figure 9 The example layout shown includes multiple layers, which allows the communication architecture to match any arbitrary battery cell / module / battery pack architecture. It should be understood that, according to some example embodiments, the RM2 can manage a single battery pack (or any number of battery packs), rather than... Figure 9The examples provided show multiple battery packs.

[0064] The description of the exemplary embodiments provided herein is presented for illustrative purposes. This description is not intended to be exhaustive or to limit the exemplary embodiments to the precise forms disclosed, and modifications and variations are possible in light of the above teachings, or may be obtained from the practice of various alternatives to the provided embodiments. The examples discussed herein were chosen and described to explain the principles and nature of the various exemplary embodiments and their practical application, enabling those skilled in the art to utilize the exemplary embodiments in various ways and with various modifications suitable for the particular intended use. Features of the embodiments described herein can be combined in all possible combinations of methods, apparatuses, modules, systems, and computer program products. It should be understood that the exemplary embodiments presented herein can be practiced in any combination of each other.

[0065] It should be noted that the word "comprising" does not necessarily exclude the presence of other elements or steps besides those listed, and the words "a" or "an" preceding an element do not exclude the presence of a plurality of such elements. Furthermore, it should be noted that any reference numerals do not limit the scope of the claims, exemplary embodiments may be implemented at least in part by both hardware and software, and several "components," "units," or "devices" may be represented by the same hardware item.

[0066] Various exemplary embodiments described herein are described in the general context of method steps or processes, which may in one aspect be implemented by a computer program product embodied in a computer-readable medium, the computer program product including computer-executable instructions such as program code that are executed by a computer in a networked environment. The computer-readable medium may include removable and non-removable storage devices, including but not limited to read-only memory (ROM), random access memory (RAM), optical disc (CD), digital versatile disc (DVD), etc. Typically, program modules may include routines, programs, objects, components, data structures, etc., that perform a particular task or implement a particular abstract data type. The computer-executable instructions, associated data structures, and program modules represent instances of program code for performing the steps of the methods disclosed herein. Specific sequences of these executable instructions or associated data structures represent instances of corresponding actions for implementing the functions described in these steps or processes.

[0067] Example embodiments have been disclosed in the accompanying drawings and description. However, many variations and modifications can be made to these embodiments. Therefore, although specific terms have been used, they are used in a general and descriptive sense only and not for limitation, and the scope of the embodiments is defined by the appended claims.

Claims

1. A communication system for monitoring a battery system, the communication system comprising: A single Time Division Multiple Access (TDMA) protocol operating across the aforementioned communication system; A plurality of electronic devices located at the first level of the communication system, wherein each electronic device is configured to obtain measurements with respect to at least one corresponding battery cell in the battery system, the plurality of electronic devices being arranged in at least two subgroups of electronic devices; At least two radio manager units located at the second level of the communication system, wherein each subgroup of electronic devices is scheduled via a first TDMA and communicates with the corresponding radio manager unit through a first communication medium; At least one radio pointer unit located at the third level of the communication system, wherein each radio manager unit and the at least one radio pointer unit are scheduled via a second TDMA and communicate via a second communication medium; The at least one radio pointer unit is configured to determine the second TDMA schedule, and each radio manager unit is configured to determine a corresponding first TDMA schedule, wherein the first TDMA schedule and the corresponding second TDMA schedule define the timing for transmitting measurement-based reporting and instruction messages synchronously throughout the communication system.

2. The communication system according to claim 1, wherein the first communication medium and the second communication medium are equivalent, or the first communication medium and the second communication medium are different.

3. The communication system according to claim 2, wherein the communication type is far-field radio, near-field radio, optical or electromagnetic medium.

4. The communication system according to claim 3, wherein the first communication medium is near-field radio and the second communication medium is far-field radio.

5. The communication system according to any one of claims 1 to 4, wherein the at least one radio manager unit includes a mechanism for switching between the first communication medium and the second communication medium.

6. The communication system according to claim 5, wherein the mechanism is an antenna switcher.

7. The communication system according to any one of claims 1 to 6, wherein: The at least one radio pointer unit is configured to transmit a broadcast message to each of the at least two radio manager units; as well as Each of the at least two radio manager units is configured to retrieve the corresponding portion of the broadcast message via a unique identifier associated with each radio manager unit.

8. The communication system according to any one of claims 1 to 7, wherein each of the plurality of electronic devices is configured to simultaneously measure at least one corresponding battery cell according to the first TDMA scheduling.

9. The communication system according to any one of claims 1 to 8, wherein the first TDMA scheduling includes at least one time frame for retrying measurements for any one of the plurality of electronic devices.

10. The communication system according to any one of claims 1 to 9, wherein the communication system is included in a battery storage facility or in an electric vehicle.

11. A method for monitoring a battery system in a communication system, the communication operating across a single Time Division Multiple Access (TDMA) protocol, the method comprising: A first TDMA schedule is determined for communication between a plurality of electronic devices and at least two radio manager units via a first communication medium, wherein the plurality of electronic devices are located at a first level of the communication system and are arranged in at least two subgroups of electronic devices, and wherein the at least two radio manager units are located at a second level of the communication medium; A second TDMA schedule is determined for communication between the at least two radio manager units and at least one radio pointer unit via a second communication medium, wherein the at least one radio pointer unit is located at the third level of the communication system; Measurements are obtained about at least one corresponding battery cell in the battery system via the plurality of electronic devices; Measurements obtained via the first TDMA scheduling and transmitted to at least two corresponding radio manager units through the first communication medium; The obtained measurements are further transmitted to the at least one radio pointer unit via the second TDMA scheduling and through the second communication medium; The at least one radio pointer unit is configured to determine the second TDMA schedule, and each radio manager unit is configured to determine a corresponding first TDMA schedule, wherein the first TDMA schedule and the corresponding second TDMA schedule define the timing for transmitting measurement-based reporting and instruction messages synchronously throughout the communication system.

12. The method of claim 11, further comprising switching between the first communication medium and the second communication medium within the at least two radio manager units.

13. The method according to any one of claims 11 to 12, the method further comprising: Broadcast messages are transmitted to each of the at least two radio manager units via the at least one radio pointer unit; as well as The corresponding portion of the broadcast message is retrieved via each of the at least two radio manager units, using a unique identifier associated with each radio manager unit.

14. The method according to any one of claims 11 to 13, wherein obtaining the measurement further comprises: At least one corresponding battery cell is simultaneously measured via the plurality of electronic devices according to the first TDMA schedule.

15. A computer-readable medium storing instructions that, when executed by a processor of a communication system for a battery system, cause the communication system to perform the method according to any one of claims 11 to 14.

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