Battery management unit

Abstract

A battery management unit (BMU) configured to communicate in parallel with a plurality of battery cell monitoring circuits (CMCs) configured to provide monitoring of a battery cell and store a chain identifier parameter initially including a predetermined default value, where the BMU is configured to perform a chain identifier parameter allocation process, the chain identifier parameter assignment process includes assigning a different chain identifier parameter to each of the plurality of CMCs, where the assigning includes using a unique ID for each CMC to individually select each of the plurality of CMCs when assigning a respective different chain identifier parameter, wherein the unique ID of each CMC is received by the BMU in response to the BMU being configured to send one or more request messages to the CMC in parallel using the predetermined default value, the one or more request messages requesting the CMC to report its unique ID to the BMU.

Description

Technical Field

[0001] The present disclosure relates to a battery management unit. It also relates to a battery management unit for managing a battery pack in combination with a plurality of battery cell monitoring circuits associated with battery cells or groups of battery cells that form at least part of the battery pack. It also relates to a plurality of battery cell monitoring circuits that communicate with a BMU; and to a system including a battery management unit and a plurality of battery cell monitoring circuits and an associated method. Background Art

[0002] A battery pack typically includes multiple battery cells or groups of battery cells, such as battery modules. A battery cell monitoring circuit, which may include a battery cell controller, is configured to monitor each battery cell or each group of battery cells. A battery management unit or BMU is configured to communicate with multiple CMCs. Providing an effective way for the BMU to communicate with the CMCs is a challenge. Summary of the invention

[0003] According to a first aspect of the present disclosure, there is provided a battery management unit (BMU) configured to communicate with a plurality of battery cell monitoring circuits, each battery cell monitoring circuit (CMC) being configured to provide monitoring of one or more battery cells and storing a chain identifier parameter initially including a predetermined default value, and wherein the battery management unit is configured to communicate with the plurality of battery cell monitoring circuits in parallel, wherein the battery management unit is configured to perform a chain identifier parameter assignment process, wherein the chain identifier parameter assignment process includes assigning different chain identifier parameters to each of a plurality of CMCs, wherein the assignment includes using a unique ID of each CMC to individually select each of the plurality of CMCs when assigning corresponding different chain identifier parameters, wherein the unique ID of each CMC is received by the BMU in response to the BMU being configured to send one or more request messages to the CMC in parallel using a predetermined default value, wherein the one or more request messages request the CMC to report its unique ID to the BMU.

[0004] In one or more embodiments, the BMU is configured to perform one or both of the following after the chain identifier parameter allocation process:

[0005] a) addressing the message to a particular CMC of the plurality of CMCs based on an assigned chain identifier parameter;

[0006] b) receiving a message from the CMC, wherein the source of the message is identified by the message containing the assigned chain identifier parameter.

[0007] In one or more embodiments, the BMU is configured to send a first request message to the CMC in parallel using a predetermined default value before assigning different chain identifier parameters and to send at least a second request message to the CMC in parallel using the predetermined default value after assigning at least one of the different chain identifier parameters, wherein the second request message includes the predetermined default value, so that the second request message is configured to be processed by the CMC that still has the chain identifier parameter set to the predetermined default value and ignored by at least one CMC that is assigned one of the different chain identifier parameters.

[0008] In one or more embodiments, the chain identifier parameter assignment process includes:

[0009] Transmitting a first request message of the one or more request messages to the plurality of battery cell monitoring circuits in parallel, the first request message comprising at least:

[0010] (i) a chain identifier value set to the predetermined default value, the chain identifier value defining which of the CMCs the first request is directed to, wherein only CMCs having a chain identifier parameter matching the chain identifier value are configured to respond to the first request; and

[0011] (ii) a request for the CMC to respond with its unique ID;

[0012] receiving, from each of the plurality of CMCs having a chain identifier parameter matching the chain identifier value, a second message including the unique ID of the CMC;

[0013] selecting a first received unique ID among the received unique IDs, and thereby selecting a first CMC among the CMCs;

[0014] Transmitting a third message to the plurality of CMCs in parallel, the third message comprising at least:

[0015] (i) an indication that the third message is intended for the CMC having a selected first one of the received unique IDs;

[0016] (ii) a request by the CMC having the selected first one of the received unique IDs to change its chain identifier parameter to a first assigned value determined by the BMU;

[0017] performing another allocation procedure for each of the remaining portion of the plurality of CMCs, comprising selecting a different one of the received unique IDs than a received unique ID previously selected during the chain identifier parameter allocation procedure and thereby selecting a different one of the CMCs; and transmitting another message to the plurality of CMCs in parallel, the another message comprising at least:

[0018] (i) an indication that the another message is intended for the different one of the CMCs having a selected different one of the received unique IDs; and

[0019] (ii) a request by the CMC having the selected different one of the received unique IDs to change its chain identifier parameter to another allocated value determined by the BMU, the other allocated value being different from the first allocated value and any other allocated value used during the other allocation process.

[0020] In one or more embodiments, the selecting a first received unique ID among the received unique IDs includes selecting a received unique ID corresponding to the second message that is first received by the BMU.

[0021] In one or more embodiments, the another assignment process includes transmitting another first request message prior to selecting a received unique ID among the received unique IDs that is different from a received unique ID previously selected during the chain identifier parameter assignment process.

[0022] In one or more embodiments, another first request message is sent each time before selecting a different one of the received unique IDs than a received unique ID previously selected during the chain identifier parameter assignment procedure.

[0023] In one or more embodiments, each time a BMU requests a corresponding CMC to change its chain identifier parameter, another allocated value is determined by the BMU incrementing the first allocated value and then incrementing each another allocated value.

[0024] In one or more embodiments, the BMU is configured to retransmit the first message if the second message is not successfully received after a predetermined maximum delay period.

[0025] According to a second aspect of the disclosure, we provide a battery cell monitoring circuit CMC configured to communicate with a battery management unit BMU together with a plurality of other CMCs, each CMC comprising an integrated circuit configured to provide monitoring of one or more battery cells and to store a chain identifier parameter initially comprising a predetermined default value, wherein the CMC is configured to determine, in response to a first message from the BMU, whether the chain identifier parameter indicated in the message matches a chain identifier parameter of the CMC, and if there is a match, process the first message, and if there is no match, ignore the message;

[0026] The integrated circuit of the CMC further includes a unique ID, and the CMC, when processing the first message, is configured to report the unique ID to the BMU in a second message in response to the first message requesting reporting of its unique ID.

[0027] In one or more embodiments, the integrated circuit of the CMC is configured to transmit the second message after expiration of the randomly set delay period.

[0028] In one or more embodiments, the integrated circuit is configured to receive a third message or another message in parallel with a plurality of CMCs, the third message or another message comprising at least:

[0029] (i) an indication that the third message or another message is intended for the CMC having a specified unique ID;

[0030] (ii) a request by the CMC having the designated unique ID to change its chain identifier parameter to a first or another assigned value determined by the BMU;

[0031] wherein the CMC is configured to determine, in response to the third message or another message from the BMU, whether the unique ID indicated in the message matches the unique ID of the integrated circuit of the CMC, and if there is a match, process the third or another message by changing the chain identifier parameter to the first or another assigned value stated in the third or another message, and if there is no match, ignore the message.

[0032] According to one aspect of the present disclosure, we provide a system comprising:

[0033] The BMU of the first aspect; and

[0034] Multiple CMCs of the second aspect.

[0035] In one or more embodiments, the system further includes a battery pack including one or both of a plurality of battery cells and a plurality of battery cell groups, wherein the plurality of CMCs are each associated with a respective one of the plurality of battery cells and the plurality of battery cell groups.

[0036] According to one aspect of the present disclosure, we provide a method for a battery management unit BMU for allocating chain identifier parameters, wherein the BMU is configured to communicate with a plurality of battery cell monitoring circuits, each battery cell monitoring circuit CMC is configured to provide monitoring of one or more battery cells and store corresponding chain identifier parameters initially including predetermined default values, and wherein the battery management unit is configured to communicate with the plurality of battery cell monitoring circuits in parallel, wherein the battery management unit is configured to perform a chain identifier parameter allocation process, the chain identifier parameter allocation process comprising:

[0037] sending one or more request messages to the CMCs in parallel using the predetermined default value, the one or more request messages requesting the CMCs to report a unique ID associated with each CMC to the BMU;

[0038] receiving, by the BMU, the unique ID of each CMC;

[0039] A different chain identifier parameter is assigned to each of the plurality of CMCs, wherein the assigning includes using the unique ID of each CMC to individually select each of the plurality of CMCs when assigning a corresponding different chain identifier parameter.

[0040] In one or more embodiments, the method includes the BMU addressing a message to a specific CMC among the plurality of CMCs based on the assigned chain identifier parameter after the chain identifier parameter assignment process.

[0041] In one or more embodiments, the method includes the BMU receiving a message from the CMC after the chain identifier parameter allocation process, wherein the source of the message is identified by the message containing the allocated chain identifier parameter.

[0042] In one or more embodiments, the method includes the BMU sending a first request message in parallel to the CMC using a predetermined default value before assigning different chain identifier parameters and sending at least a second request message in parallel to the CMC using the predetermined default value after assigning at least one of the different chain identifier parameters, wherein the second request message includes the predetermined default value, so that the second request message is configured to be processed by the CMC that still has the chain identifier parameter set to the predetermined default value and ignored by at least one CMC that is assigned one of the different chain identifier parameters.

[0043] In one or more embodiments, the method includes sending a plurality of second request messages each time after assigning one or more of the different chain identifier parameters until a plurality of CMCs have been assigned.

[0044] Although the present disclosure allows for various modifications and alternative forms, the details thereof have been shown in the drawings by way of example and will be described in detail. However, it should be understood that other embodiments other than the specific embodiments described may also exist. All modifications, equivalents, and alternative embodiments falling within the spirit and scope of the appended claims are also encompassed.

[0045] The above discussion is not intended to present every exemplary embodiment or every implementation within the scope of the current or future claim sets. The drawings and detailed description also illustrate various exemplary embodiments. Various exemplary embodiments may be more fully understood by considering the following detailed description in conjunction with the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] One or more embodiments will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0047] Figure 1 An example of a battery management unit communicatively coupled to a plurality of battery cell monitoring circuits in a series connected network topology is shown;

[0048] Figure 2 An exemplary embodiment of the present disclosure is shown, which includes a system including a battery management unit communicatively coupled to a plurality of battery cell monitoring circuits in a communication network arranged in parallel;

[0049] Figure 3 An exemplary flow chart is shown, which shows Figure 2 The operation of the battery management unit;

[0050] Figure 4 A first exemplary flow chart is shown, which shows Figure 2 The operation of the battery cell monitoring circuit; and

[0051] Figure 5 A second exemplary flow chart is shown, which shows Figure 2 Operation of the battery cell monitoring circuit. DETAILED DESCRIPTION

[0052] In a rapidly growing market environment, battery management systems are constantly evolving due to the need for higher energy density, higher reliability and higher safety levels. This leads to the need for new features in high-performance communication systems, such as communication systems with high synchronization.

[0053] For example, a communication system may be required to allow communication between various "slave" or cell monitoring circuits that are performing measurements (eg, electrochemical spectroscopy measurements) and a battery management unit. In other examples, a communication system may be required to provide a reconfigurable battery.

[0054] Figure 1 A system 100 is shown that includes a battery pack and a communication system.

[0055] The battery pack typically includes several modules, groups of cells 101, 102, 103 or individual cells, each of which is monitored by a cell monitoring circuit (CMC) 104, 105, 106. Typically, a master control unit (often referred to as a battery management unit (BMU) 107) communicates with "slave" CMCs, which are connected in a "daisy chain" fashion including a chain connected in series. The communication protocol in use typically does not include conflict management.

[0056] For manufacturability reasons, it is usually required that all CMCs 104, 105, 106 are identical and therefore do not include an identifier that can identify their position within the series-connected chain. Therefore, a daisy chain initialization process is required to allow identification of all nodes within the chain (so-called "enumeration"). At the end of the enumeration process, each node should have a unique chain identifier ID (sometimes referred to as a chain identifier or CID). The ownership of this CID is managed by the BMU at power-up of the system 100 or after any reset event.

[0057] For a communication system comprising a chain of serial connections, the enumeration process can be implemented by the BMU requesting the unenumerated node not to propagate the message sent by the BMU to implement the enumeration to the next node in the daisy chain. Thus, the nodes can be enumerated one by one and thus assigned a CID. This automatic enumeration process can only be used with a BMU having Figure 1 The series topology shown is implemented as a daisy chain.

[0058] However, there are some limitations to the series-connected chain communication wiring 110 topology. For example, it is known that the battery cell controller or CMC present in the CMC is usually characterized by a repeater function, which relays the message to the adjacent CMC in the chain. It has been found that the use of repeaters increases the delay of message propagation to the next node. This delay can be about 1 μs per node and may also be prone to variation due to digital jitter. This delay may hinder accurate synchronous operation within the series-connected chain. In other examples, in the case where the BCC does not have a repeater function, the BCC may include a switch that is used to disconnect the rest of the chain and terminate the chain when the CMC is not enumerated to avoid reflections. However, the resistance of the series-connected switches and the insertion loss of the transformers 111 and 112 contribute to the attenuation of the signal at each node, which accumulates along the series-connected chain. This limits the number of nodes that can be connected to a single daisy chain to about ten to fifteen, depending on various parameters (such as signal strength, wiring cable length and quality). In applications that require low node-to-node delay and long daisy chains, the series-connected chain topology is suboptimal.

[0059] Therefore, a parallel connected communication network between CMCs may be preferred.However, as already mentioned, in many instances, the CMCs cannot be efficiently enumerated when they are arranged in a parallel communication topology.

[0060] This embodiment of the present disclosure relates to a BMU configured to communicate with a CMC via a communication network arranged in parallel, such as Figure 2 In a communication network arranged in parallel, a message sent by a BMU is transmitted to all CMCs coupled to the communication network arranged in parallel without the need for the message to be relayed along a chain of CMCs by action of the CMC.

[0061] Figure 2 A system 200 is shown that includes a plurality of battery cells 201, wherein respective groups of these battery cells 201 are monitored by a plurality of battery cell monitoring circuits or CMCs 202, 203, 204. Each CMC 202, 203, 204 may include one or more battery cell controllers 205, 206, 207. The CMCs 202, 203, 204 in this example are each coupled to a parallel arranged communication network 215 by transformers 208, 209, 210, but other galvanic isolation may be provided. The parallel arranged communication network is provided by twisted pair wires with parallel branches to couple to the transformers 208, 209, 210 of each CMC.

[0062] The system 200 includes a battery management unit BMU 211 configured to communicate with a plurality of battery cell monitoring circuits 202, 203, 204 via a parallel arranged communication network 215. The BMU 211 may include a microcontroller 212 and a physical layer block 213 that couples the microcontroller 212 to the parallel arranged communication network wiring via a transformer 214 (or other galvanic isolation). Thus, the MCU 212 may send messages to and / or receive messages from the CMC via the parallel arranged communication network.

[0063] As previously mentioned, each CMC 202, 203, 204 is configured to store a chain identifier parameter (referred to as a chain ID parameter) that is conventionally used to store a chain identifier value assigned to the CMC by the BMU in a network connected in series. The chain ID parameter is typically set to a predetermined default value at least initially at power-on or after a system reset. In some examples, the predetermined default value may include "zero".

[0064] In the present example, the battery management unit 211 is configured to communicate with the plurality of CMCs 202, 203, 204 in parallel and to perform a chain identifier parameter assignment procedure to be described below at least during an initialization period, eg, at power-up or after a reset.

[0065] The chain identifier parameter assignment process includes assigning a different chain identifier parameter to each of the plurality of CMCs 204, 205, 206. Thus, each CMC coupled to the communication network arranged in parallel is given a different chain ID assigned by the BMU, which provides for enumeration of CMCs as known in the art. The assignment is achieved by individually selecting each of the plurality of CMCs using a unique ID for each CMC. Thus, the unique ID is used to ensure that the BMU 211 indicates a single CMC 202, 203, 204 when assigning the corresponding different chain identifier parameters.

[0066] The unique ID may be a unique ID of an integrated circuit of the CMC (e.g., integrated circuits 205 to 207 providing battery cell controller (BCC) functionality). It is known that many integrated circuits have a unique ID (UID) that is typically distributed over several registers (e.g., 2 to 3), and IC manufacturers typically ensure that the UID is unique over a production span of more than 10 years. Therefore, it has been discovered that the uniqueness of the unique ID of each integrated circuit can be used to select a single CMC and thereby uniquely assign a chain identifier parameter in a communication network arranged in parallel.

[0067] The unique ID of each CMC 202, 203, 204 is received by the BMU 211 in response to the BMU 211 being configured to send one or more request messages to the CMC in parallel using predetermined default values, the one or more request messages requesting the CMC to report its unique ID to the BMU 211. Thus, the BMU may be configured to send one or more request messages over the parallel communication network that specify the predetermined default values ​​and that will therefore be processed by a CMC whose chain identifier parameter is set to the predetermined default value (and not by a CMC whose chain identifier parameter is not set to the predetermined default value). Interpreting the request messages and in response, reading from one or more registers storing the unique ID, generating a reply message containing the unique ID, and transmitting the reply message to the BMU 211 may be standard functionality of the CMCs 202, 203, 204. These actions of the CMC will be described in more detail later.

[0068] Assigning a different chain identifier parameter to each of the CMCs makes them individually addressable, thereby improving the performance of the parallel-connected communication network.

[0069] Thus, after the chain identifier parameter assignment process, the BMU may be configured to address future messages to a particular CMC among the plurality of CMCs based on the assigned chain identifier parameter.Alternatively or additionally, the BMU 211 may be configured to receive messages from a CMC, wherein the source of the message is identified by the message containing the assigned chain identifier parameter.

[0070] The CMCs 202, 203, 204 may be configured to generate a message called t before transmitting the reply message to the BMU 211. delay The random timer value is set to t delay Each CMC may be configured to wait until the delay counter has reached its t before transmitting a reply message. delay There may be a maximum delay period, and during this maximum delay period, if the BMU 211 receives a reply message, the BMU may then use the unique ID contained in the reply message to assign a chain identifier parameter such that the assignment is applicable to one of the CMCs. In some examples, the BMU 211 may be configured (e.g., from the time when the shortest t delay In one embodiment, the BMU 211 receives the first reply message from the CMC of the plurality of received reply messages, and then stops processing any later received reply messages. In other examples, the BMU 211 may be configured to collate multiple unique IDs from the corresponding plurality of received reply messages to individually select each of the plurality of CMCs in turn before using the unique ID received in each of those reply messages to assign different chain identifier parameters.

[0071] It should be appreciated that without conflict management, reply messages from multiple CMCs 202, 203, 204 may be transmitted simultaneously and thus may be corrupted on the communication network arranged in parallel. Therefore, in one or more examples, the BMU 211 may be configured to send multiple request messages. Considering t delay The number of request messages sent may be randomly generated, and sending multiple request messages may increase the probability of successfully receiving reply messages (i.e., consecutive request messages) from all CMCs over time. It has also been recognized that only CMCs whose chain identifier parameters are set to the default value will respond to multiple request messages. Therefore, the BMU 107 may be configured to send a request message after each assignment (or a predetermined number of assignments) of a different chain identifier parameter. In this way, the probability of a conflict is reduced because the number of CMCs that respond to the request message is also reduced because the CMC is assigned a chain identifier parameter that is different from the predetermined default value.

[0072] Thus, generally speaking, as an illustrative example, BMU 211 is configured to send a first request message in parallel to CMCs 202 to 204 using the predetermined default values ​​before assigning different chain identifier parameters to, say, CMC 202. Thus, CMCs 202 to 204 will respond, with some or all of the reply messages being successfully received by BMU 211. BMU 211 may be configured to send at least a second request message after assigning different chain identifier parameters to CMC 202, wherein the second request message includes the predetermined default values, such that the second request message is configured to be processed by CMCs that still have chain identifier parameters set to the predetermined default values ​​(i.e., CMCs 203 and 204 in this example). CMC 202 has already been assigned chain identifier parameters that are different from the predetermined default values, and therefore may ignore the second request message.

[0073] Now refer to Figure 3 The exemplary flowchart of describes the chain identifier parameter allocation process in more detail.

[0074] The chain identifier parameter assignment process includes:

[0075] Transmitting 301 a first request message of one or more request messages to a plurality of battery cell monitoring circuits 202 to 204 in parallel, the first request message comprising at least:

[0076] (i) a chain identifier value set to a predetermined default value, and

[0077] (ii) The CMC responds to the request with its unique ID.

[0078] As mentioned above, the chain identifier value in the first request message defines which of the CMCs the first request is for. Therefore, only CMCs 202 to 204 having a chain identifier parameter that matches the chain identifier value are configured to respond to the first request. Therefore, initially, it is expected that the first request message will be processed and responded to by all CMCs 202 to 204 because the default value is used and initially, all CMCs have the default value for their chain identifier parameter.

[0079] Next, the BMU 211 is configured to receive 302 from each of the plurality of CMCs having a chain identifier parameter matching the chain identifier value a second message containing the unique ID of the CMC.

[0080] In this example, the BMU is configured to act on the first received second message. However, in other examples, the BMU 211 may receive multiple second messages.

[0081] Next, BMU 211 is configured to select 303 a first received unique ID among the received unique IDs (reported in the second message). In selecting the received unique ID, BMU 211 effectively selects a first one of the CMCs, such as CMC 202 .

[0082] Next, the BMU 211 is configured to transmit 304 a third message to the plurality of CMCs in parallel, the third message comprising at least:

[0083] (i) an indication that the third message is intended for the CMC having a selected first one of the received unique IDs;

[0084] (ii) A request for the CMC having the selected first one of the received unique IDs to change its chain identifier parameter to a first assigned value determined by the BMU.

[0085] Thus, if the predetermined default value of the chain identifier parameter is zero, the third request may instruct CMC 202 to change its chain identifier parameter to "1".

[0086] Next, the BMU 211 is configured to perform another assignment process. In practice, the other assignment process continuously moves through other unique IDs to assign different chain identifier parameters to each of the remaining CMCs 203 and 204.

[0087] Thus, for each of the remaining plurality of CMCs (i.e., CMCs 203, 204), BMU 211 is configured to select 305 a received unique ID from the received unique IDs that is different from the received unique ID previously selected during the chain identifier parameter allocation process, and thereby select a different CMC from the CMCs, such as CMC 203.

[0088] Next, the BMU 211 is configured to transmit 306 another message to the plurality of CMCs in parallel, the another message comprising at least:

[0089] (i) an indication that the further message is intended for a different one of the CMCs having a selected different one of the received unique IDs (CMC 203 in this example); and

[0090] (ii) A request by the CMC 203 having a selected different one of the received unique IDs to change its chain identifier parameter to another assigned value determined by the BMU that is different from the first assigned value and any other another assigned value used during another assignment process.

[0091] Another message may instruct CMC 203 to change its chain identifier parameter to “2.” Thus, BMU 211 may determine another assigned value by incrementing the previously assigned value.

[0092] The BMU is then configured to repeat 307 another allocation process for the remaining CMCs (which in this example is CMC 204) with a predetermined default value of zero.

[0093] Therefore, the BMU 211 is configured to select 305 a different one of the received unique IDs than the one previously selected during the chain identifier parameter allocation procedure, and thereby select a different one of the CMCs, which in this example is the last remaining CMC 204 .

[0094] Next, the BMU 211 is configured to transmit 306 another further message to the plurality of CMCs in parallel, the further message comprising at least:

[0095] (i) an indication that the further message is intended for a different one of the CMCs (CMC 204 in this iteration of the further allocation process) having a selected different one of the received unique IDs; and

[0096] (ii) A request for the CMC 204 having a selected different one of the received unique IDs to change its chain identifier parameter to another assigned value determined by the BMU that is different from the first assigned value and any other another assigned value used during another assignment process.

[0097] The other message may instruct CMC 204 to change its chain identifier parameter to "3" (incremented from "2," which was assigned in the previous iteration).

[0098] In one or more examples, the other message described above also includes a chain identifier parameter value set to a predetermined default value.

[0099] When all CMCs have been assigned chain identifier parameters, the BMU 211 may be configured to end 308 the chain identifier parameter assignment process. Ending may be determined by not receiving a response to the transmission of the first message.

[0100] Another allocation process may include the BMU 211 being configured to transmit 309 another first request message (and receiving in a second message the remaining unique IDs for CMCs that still have the predetermined default value for their chain identifier parameters) before selecting 305 one of the received unique IDs that is different from the one previously selected during the chain identifier parameter allocation process. Thus, the selecting step 305 may include selecting one of the unique IDs received in response to transmitting 309 the most recent of the another first request message.

[0101] In the present example, the BMU 211 is configured to transmit 309 another first request message each time before selecting 305 a received unique ID that is different from a received unique ID previously selected during the chain identifier parameter allocation process. In other examples, multiple unique IDs may be collated from multiple received second messages, and thus each transmission 309 of another first request message may not be necessary.

[0102] Taking into account the lack of conflict management, BMU 211 can be configured to retransmit the first message if the second message is not successfully received after a predetermined maximum delay period. Retransmitting the first message (or another first message) will prompt the CMC to generate a different T delay , so there might not be a conflict next time.

[0103] Now refer to Figure 4 and Figure 5 The chain identifier parameter allocation process is described from the perspective of any one of the CMCs 202 to 204 .

[0104] Therefore, to restate the configuration of the components, each CMC 202 to 204 is configured to communicate with the battery management unit BMU 211 as well as a plurality of other CMCs.

[0105] Each CMC 202-204 includes an integrated circuit 205-207, which may include a BCC, configured to provide monitoring of one or more battery cells 201. The integrated circuit 205-207, or CMC more generally, may store a chain identifier parameter that initially includes a predetermined default value.

[0106] The CMC 202 to 204 is configured to read 401 a unique ID from its register in response to the first message or another first message. The reading of the register may include an error checking step 402, such as a cyclic redundancy check (CRC) verification process. If the CRC fails, the reading 401 is performed again. If the CRC is OK, then in response to the first message from the BMU 211, the CMC 202 to 204 is configured to determine 403 whether the chain identifier parameter indicated in the message matches the chain identifier parameter of the CMC.

[0107] If there is no match, the CMC ignores 404 the first message (or the further first message) or because the node has already been enumerated.If there is a match, the CMC is configured to continue processing the first message or the further first message including the enumeration request.

[0108] Processing the first message or another first message includes the CMC being configured to report its unique ID (read at 401 ) to the BMU in a second message in response to the first message requesting reporting of the unique ID.

[0109] This is done by CMC generating a random T at 405 delay The counters of ICs 205 to 207 are set at 406 to T delay At 407 , the CMC waits for another 1 μs.

[0110] Step 408 shows the counter from T delay Decreasing (or towards T delay Incremented so that the delay period is counted out, regardless of how the counter is implemented).

[0111] At step 409, if any bus activity is detected before the counter equals zero, the CMC aborts sending the second message.

[0112] If no bus activity is detected while the counter is equal to zero 410, the CMC transmits the contents of the UID register to the BMU in a second message 411.

[0113] refer to Figure 5, the CMC 202 to 204 is configured to receive 501 a third message or another message, wherein the third message or another message comprises at least:

[0114] (i) an indication that the third message or another message is intended for the CMC having a specified unique ID;

[0115] (ii) A request by the CMC having the designated unique ID to change its chain identifier parameter to a first or another assigned value determined by the BMU.

[0116] An error checking step may be performed at 502 .

[0117] At 503, the CMC is further configured to determine whether the unique ID indicated in the message matches the unique ID of the integrated circuit of the CMC.

[0118] At step 505, if there is a match, the CMCs 202 to 204 are configured to process the third or further message by changing its chain identifier parameter to the first or further assigned value stated in the third or further message.

[0119] If there is no match for the unique ID, the CMC may ignore the message and the process performed by the CMC returns to step 501 .

[0120] It should be understood that a system 200 is also disclosed that includes a BMU 211 and a plurality of CMCs 202 through 204. The system 200 may be coupled to a battery pack 201 such that the CMCs are each associated with a respective one of a plurality of battery cells and a plurality of battery cell groups.

[0121] Unless a specific order is explicitly stated, the instructions and / or flow chart steps in the above figures may be performed in any order. Moreover, those skilled in the art will recognize that although an exemplary instruction set / method has been discussed, the materials in this specification may be combined in a variety of ways to produce other examples and should be understood within the context provided in this detailed description.

[0122] In some exemplary embodiments, the instruction set / method steps described above are implemented as functions and software instructions embodied as an executable instruction set, which is implemented on a computer or a machine programmed and controlled with the executable instructions. Such instructions are loaded for execution on a processor (e.g., one or more CPUs). The term processor includes a microprocessor, a microcontroller, a processor module or subsystem (including one or more microprocessors or microcontrollers), or other control or computing devices. A processor may refer to a single component or multiple components.

[0123] In other examples, the instruction sets / methods shown herein and the data and instructions associated therewith are stored in corresponding storage devices, which are implemented as one or more non-transitory machine or computer readable or computer usable storage media. Such computer readable or computer usable storage media are considered to be part of an article (or product). An article or product may refer to any manufactured single component or multiple components. Non-transitory machine or computer usable media as defined herein do not include signals, but such media may be able to receive and process information from signals and / or other transient media.

[0124] Exemplary embodiments of the materials discussed in this specification may be implemented in whole or in part via a network, computer or data-based device and / or service. These may include the cloud, the Internet, an intranet, a mobile device, a desktop computer, a processor, a lookup table, a microcontroller, a consumer device, an infrastructure, or other enabling devices and services. As may be used herein and in the claims, the following non-exclusive definitions are provided.

[0125] In one example, one or more instructions or steps discussed herein are automated. The term automation or automatically (and similar variations thereof) means the use of computers and / or mechanical / electrical devices to control the operation of a device, system, and / or process without human intervention, observation, effort, and / or decision making.

[0126] It should be understood that any components that are said to be coupled can be coupled or connected directly or indirectly. In the case of indirect coupling, additional components can be placed between the two components that are said to be coupled.

[0127] In this specification, exemplary embodiments have been presented in a selected set of details. However, one of ordinary skill in the art will appreciate that many other exemplary embodiments may be practiced that include different selected sets of these details. It is intended that the appended claims cover all possible exemplary embodiments.

Claims

1. A battery management unit BMU, characterized in that: The BMU is configured to communicate with a plurality of battery cell monitoring circuits, each battery cell monitoring circuit CMC being configured to provide monitoring of one or more battery cells and store a chain identifier parameter initially including a predetermined default value, and wherein the battery management unit is configured to communicate in parallel with the plurality of battery cell monitoring circuits, wherein the battery management unit is configured to perform a chain identifier parameter assignment process, the chain identifier parameter assignment process comprising assigning different chain identifier parameters to each of the plurality of CMCs, wherein the assignment comprises using a unique ID of each CMC to individually select each of the plurality of CMCs when assigning corresponding different chain identifier parameters, wherein the unique ID of each CMC is received by the BMU in response to the BMU being configured to send one or more request messages to the CMC in parallel using the predetermined default value, the one or more request messages requesting the CMC to report its unique ID to the BMU.

2. The battery management unit according to claim 1, characterized in that: The BMU is configured to perform one or both of the following after the chain identifier parameter allocation process: a) addressing the message to a particular CMC among the plurality of CMCs based on an assigned chain identifier parameter; b) receiving a message from the CMC, wherein the source of the message is identified by the message containing the assigned chain identifier parameter.

3. The battery management unit according to claim 1 or claim 2, characterized in that: The BMU is configured to send a first request message to the CMC in parallel using the predetermined default value before assigning the different chain identifier parameters and to send at least a second request message to the CMC in parallel using the predetermined default value after assigning at least one of the different chain identifier parameters, wherein the second request message includes the predetermined default value, so that the second request message is configured to be processed by the CMC that still has the chain identifier parameter set to the predetermined default value and ignored by at least one CMC that has been assigned one of the different chain identifier parameters.

4. The battery management unit according to claim 1 or claim 2, characterized in that: The chain identifier parameter allocation process includes: Transmitting a first request message of the one or more request messages to the plurality of battery cell monitoring circuits in parallel, the first request message comprising at least: (i) a chain identifier value set to the predetermined default value, the chain identifier value defining which of the CMCs the first request is directed to, wherein only CMCs having a chain identifier parameter matching the chain identifier value are configured to respond to the first request; and (ii) a request for the CMC to respond with its unique ID; receiving, from each of the plurality of CMCs having a chain identifier parameter matching the chain identifier value, a second message including the unique ID of the CMC; selecting a first received unique ID among the received unique IDs, and thereby selecting a first CMC among the CMCs; Transmitting a third message to the plurality of CMCs in parallel, the third message comprising at least: (i) an indication that the third message is intended for the CMC having a selected first one of the received unique IDs; (ii) a request by the CMC having the selected first one of the received unique IDs to change its chain identifier parameter to a first assigned value determined by the BMU; performing another allocation procedure for each of the remaining portion of the plurality of CMCs, comprising selecting a different one of the received unique IDs than a received unique ID previously selected during the chain identifier parameter allocation procedure and thereby selecting a different one of the CMCs; and transmitting another message to the plurality of CMCs in parallel, the another message comprising at least: (i) an indication that the another message is intended for the different one of the CMCs having a selected different one of the received unique IDs; and (ii) a request by the CMC having the selected different one of the received unique IDs to change its chain identifier parameter to another allocated value determined by the BMU, the other allocated value being different from the first allocated value and any other allocated value used during the other allocation process.

5. The battery management unit according to claim 4, characterized in that: The selecting the first of the received unique IDs includes selecting the received unique ID corresponding to the second message that is first received by the BMU.

6. The battery management unit according to claim 4 or claim 5, characterized in that: The further assignment procedure comprises transmitting a further first request message prior to said selecting one of the received unique IDs that is different from a received unique ID previously selected during the chain identifier parameter assignment procedure.

7. The battery management unit according to claim 6, characterized in that: The further first request message is sent each time before the selecting of the received unique ID that is different from a received unique ID previously selected during the chain identifier parameter allocation procedure.

8. A battery cell monitoring circuit CMC, characterized in that: the CMC being configured to communicate with a battery management unit (BMU) along with a plurality of other CMCs, each CMC comprising an integrated circuit configured to provide monitoring of one or more battery cells and to store a chain identifier parameter that initially comprises a predetermined default value, wherein the CMC is configured to determine, in response to a first message from the BMU, whether the chain identifier parameter indicated in the message matches the chain identifier parameter of the CMC, and if there is a match, process the first message, and if there is no match, ignore the message; The integrated circuit of the CMC further includes a unique ID, and the CMC, when processing the first message, is configured to report the unique ID to the BMU in a second message in response to the first message requesting reporting of its unique ID.

9. A system, characterized in that: The system comprises: A BMU according to any one of claims 1 to 9; and A plurality of CMCs according to any one of claims 10 to 12.

10. A method for a battery management unit (BMU) for allocating chain identifier parameters, characterized in that: The BMU is configured to communicate with a plurality of battery cell monitoring circuits, each battery cell monitoring circuit CMC is configured to provide monitoring of one or more battery cells and store a corresponding chain identifier parameter initially including a predetermined default value, and wherein the battery management unit is configured to communicate in parallel with the plurality of battery cell monitoring circuits, wherein the battery management unit is configured to perform a chain identifier parameter allocation process, the chain identifier parameter allocation process comprising: sending one or more request messages to the CMCs in parallel using the predetermined default value, the one or more request messages requesting the CMCs to report a unique ID associated with each CMC to the BMU; receiving, by the BMU, the unique ID of each CMC; A different chain identifier parameter is assigned to each of the plurality of CMCs, wherein the assigning includes using the unique ID of each CMC to individually select each of the plurality of CMCs when assigning a corresponding different chain identifier parameter.

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