Battery management system and electric vehicle

Abstract

The utility model relates to the technical field of batteries, and discloses a battery management system and an electric vehicle, and the system comprises a master battery control module and m slave battery control modules, the m slave battery control modules are connected in parallel, the master battery control module is in bidirectional communication connection with the slave battery control modules, the master battery control module is used for sending sampling instructions to the slave battery control modules, and the slave battery control modules are used for sending sampled battery data to the master battery control module; each slave battery control module comprises n sampling units; the target sampling unit is connected with the main battery control module, the target sampling unit is used for sending battery data collected by each sampling unit to the main battery control module, and the target sampling unit is any one of m sampling units. The problem of long sampling period in the prior art is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery management system and an electric vehicle. Background Art

[0002] The battery management system (BMS) of an electric vehicle is a crucial link between the onboard power battery and the electric vehicle. Its primary functions include battery status detection and analysis, battery safety protection, energy control and management, and battery information management. BMSs are primarily available in two architectures: integrated and master-slave. The master-slave architecture consists of a master control unit (BCU) and a slave control unit (SCU). The BCU and SCU typically communicate using two methods: CAN communication and daisy-chain differential signaling.

[0003] CAN communication transmits data via the CAN bus and has high reliability and anti-interference capabilities. However, each communication node in this solution requires an MCU and a transceiver chip. When there are too many nodes, the circuit cost also increases. It also causes the communication line to be too long, resulting in severe attenuation of the CAN waveform amplitude and excessive bus load rate, which makes the bus bit error rate high and the communication unstable.

[0004] Daisy-chain communication, based on a single ASIC (Application Specific Integrated Circuit) sampling circuit and using a cascaded connection, allows for simultaneous or selective communication on this communication line. ASICs can also be automatically numbered and identified, eliminating the need for hardware numbering of sub-boards. This makes the circuit simple, easy to implement, and low-cost, suitable for multi-node communication, making it the current mainstream communication solution. However, because each communication node is connected in series, data transmission must be performed node by node, resulting in a longer sampling period and a lower overall BMS sampling rate. Utility Model Content

[0005] In view of this, the present invention provides a battery management system and an electric vehicle to solve the problem of long sampling period in the prior art.

[0006] In a first aspect, the present invention provides a battery management system, the system comprising:

[0007] A master battery control module and m slave battery control modules, where m ≥ 1;

[0008] m slave battery control modules are connected in parallel, and the master battery control module is connected to each slave battery control module in a two-way communication manner, wherein the master battery control module is used to send sampling instructions to the slave battery control module, and the slave battery control module is used to send sampled battery data to the master battery control module;

[0009] Each slave battery control module includes n sampling units, where n>1;

[0010] The target sampling unit is connected to the main battery control module and is used to send the battery data collected by each sampling unit to the main battery control module, wherein the target sampling unit is any one of the n sampling units.

[0011] The battery management system provided by the present invention saves sampling time because each slave battery control module sends the battery data of the sampling unit to the master battery control module respectively, thereby greatly saving the sampling cycle.

[0012] In an optional embodiment, the sampling units are connected in a ring topology, and the first sampling unit is connected to the main battery control module as a target sampling unit;

[0013] The first sampling unit receives the sampling instruction, collects the first battery data, and sends the first battery data to the second sampling unit;

[0014] The second sampling unit collects the second battery data and sends the first battery data and the second battery data to the third sampling unit;

[0015] Until the nth sampling unit sends the first battery data to the nth battery data to the first sampling unit, the first sampling unit sends each battery data to the main battery control module.

[0016] In an optional embodiment, the sampling units are interconnected to form a plurality of connected ring topological connections.

[0017] In an optional embodiment, the slave battery control modules are connected in series via a sampling unit.

[0018] In an optional implementation, the first sampling unit of the mth slave battery control module is connected to the xth sampling unit of the (m-1)th slave battery control module, where m>1.

[0019] In an optional embodiment, the main battery control module includes: a communication unit and a main control unit;

[0020] The first end of the communication unit is connected to the main control unit, and the second end of the communication unit is connected to the slave battery control module. The communication unit is used to send sampling instructions to the slave battery control module and send sampled battery data to the main control unit.

[0021] In an optional embodiment, the communication unit includes:

[0022] A bidirectional bridge chip is connected to the main control unit and the slave battery control module respectively. The bidirectional bridge chip is used to send sampling instructions to the slave battery control module and send sampled battery data to the main control unit.

[0023] In an optional embodiment, the communication unit includes: a first bridge chip and a second bridge chip;

[0024] The first bridge chip is connected to each slave battery control module and the main control unit respectively, and the first bridge chip is used to send a sampling instruction to each slave battery control module;

[0025] The second bridge chip is connected to each slave battery control module and the main control unit respectively, and the second bridge chip is used to send the battery data of each slave battery control module to the main control unit.

[0026] In an optional implementation, each sampling unit is connected to one or more battery cells, and the sampling unit collects battery data of the one or more battery cells.

[0027] In a second aspect, the present invention provides an electric vehicle, which includes the above battery management system. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0029] Figure 1 This is the structural diagram of a traditional series battery management system;

[0030] Figure 2 is a structural diagram of a battery management system according to an embodiment of the present utility model;

[0031] Figure 3 is a structural diagram of another battery management system according to an embodiment of the present utility model;

[0032] Figure 4 This is a structural diagram of a sampling unit in a battery management system according to an embodiment of the present utility model;

[0033] Figure 5 is an application diagram of a battery management system according to an embodiment of the present utility model;

[0034] Figure 6 is a structural diagram of another battery management system according to an embodiment of the present utility model;

[0035] Figure 7 1 is a schematic diagram of the communication direction of a battery management system according to an embodiment of the present utility model;

[0036] Figure 8 is a schematic diagram of the communication direction of another battery management system according to an embodiment of the present utility model;

[0037] Figure 9 This is a detailed structural diagram of a main battery control module in a battery management system according to an embodiment of the present utility model;

[0038] Figure 10 It is a collection schematic diagram of a battery management system according to an embodiment of the present utility model. DETAILED DESCRIPTION

[0039] The following is a clear and complete description of the technical solution of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0040] In the description of the present invention, it should be noted that the terms "first", "second" and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0041] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections or electrical connections; they may refer to direct connections or indirect connections through an intermediate medium; they may refer to internal connections between two components; they may refer to wireless connections or wired connections. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0042] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0043] The battery management system (BMS) of an electric vehicle is a crucial link between the onboard power battery and the electric vehicle. Its primary functions include battery status detection and analysis, battery safety protection, energy control and management, and battery information management. BMSs are primarily available in two architectures: integrated and master-slave. The master-slave architecture consists of a master control unit (BCU) and a slave control unit (SCU). The BCU and SCU typically communicate using two methods: CAN communication and daisy-chain differential signaling.

[0044] CAN communication transmits data via the CAN bus and has high reliability and anti-interference capabilities. However, each communication node in this solution requires an MCU and a transceiver chip. When there are too many nodes, the circuit cost also increases. It also causes the communication line to be too long, resulting in severe attenuation of the CAN waveform amplitude and excessive bus load rate, which makes the bus bit error rate high and the communication unstable.

[0045] Daisy chain communication is based on ASIC (Application Specific Integrated Circuit) single sampling circuit, using cascade connection method, which can communicate simultaneously or select several chips on this communication line, and can automatically number and identify ASICs, without the need for hardware numbering of sub-boards. Therefore, the circuit is simple and easy to implement, low cost, suitable for multi-node communication, and is currently the mainstream communication solution. However, if Figure 1 ,Since the nodes of the communication units are connected in series, data needs to be ,transmitted node by node, which results in a longer sampling period and a ,lower overall sampling rate of the BMS.

[0046] In this regard, a battery management system is provided in this embodiment. Figure 2 As shown, the system includes: a master battery control module A and m slave battery control modules B, where m≥1;

[0047] m slave battery control modules B are connected in parallel, each slave battery control module B is connected to a master battery control module A, and the master battery control module A is connected to each slave battery control module B in a two-way communication manner, wherein the master battery control module A is used to send sampling instructions to the slave battery control module B, and the slave battery control module B is used to send sampled battery data to the master battery control module A;

[0048] Specifically, refer to Figure 2There may be m slave battery control modules B, namely B1, B2, ..., and Bm. B1 to Bm are connected in parallel and are each connected to a master battery control module A. The master battery control module A sends a sampling instruction to B1 to Bm, and B1 to Bm send their collected battery data to the master battery control module A.

[0049] Each slave battery control module B includes n sampling units C, where n>1;

[0050] The target sampling unit is connected to the main battery control module A. The target sampling unit is used to send the battery data collected by each sampling unit to the main battery control module A. The target sampling unit is any one of the n sampling units C.

[0051] Specifically, refer to Figure 2 , the number of sampling units C in B1 can be n, namely C11, C12, ..., C1n; the number of sampling units C in B2 can be n, namely C21, C22, ..., C2n; and so on. The number of sampling units C in Bm can be n, namely Cm1, Cm2, ..., Cmn. The target sampling unit in B1 collects the battery data collected by each sampling unit C, that is, collects the battery data collected by C11, C12, ..., C1n, and sends the battery data collected by C11, C12, ..., C1n to the main battery control module A. Optionally, in B1, the target sampling unit can be any one of C11, C12, ..., C1n; in B2, the target sampling unit can be any one of C21, C22, ..., C2n, and so on.

[0052] refer to Figure 1 In a traditional battery management system, a sampling period for an electric vehicle battery management system consisting of m SCUs (slave control units) with n sampling units is m*nT. However, in the battery management system provided by the present invention, each slave battery control module sends battery data from n sampling units to the master battery control module, saving mT of time and significantly shortening the sampling period.

[0053] In some optional embodiments, reference Figure 3 , each sampling unit C is connected in a ring topology, and the first sampling unit C is connected to the main battery control module A as the target sampling unit;

[0054] The first sampling unit C receives the sampling instruction, collects the first battery data, and sends the first battery data to the second sampling unit C;

[0055] The second sampling unit C collects the second battery data and sends the first battery data and the second battery data to the third sampling unit C;

[0056] Until the nth sampling unit C sends the first battery data to the nth battery data to the first sampling unit, the first sampling unit C sends each battery data to the main battery control module A.

[0057] Specifically, refer to Figure 3 In B1, C11, C12...C1n are connected in sequence to form a ring. C11 collects the first battery data of B1 and sends it to C12. C12 collects the second battery data of B1 and sends it to C13. And so on, until C1n sends the first to nth battery data collected by C11, C12...C1n to the main battery control module A.

[0058] In B2, C21, C22...C2n are connected in sequence to form a ring. C21 collects the first battery data of B2 and sends it to C22. C22 collects the second battery data of B2 and sends it to C23, and so on, until C2n sends the first to nth battery data collected by C21, C22...C2n to the main battery control module A.

[0059] Therefore, the sampling time of each slave battery control module B is nT, and each slave battery control module B sends the collected battery data of each slave battery control module B to the master battery control module A. Therefore, a sampling cycle of the battery management system is nT, which greatly saves sampling time.

[0060] In some optional embodiments, such as Figure 4 and Figure 5 As shown, the sampling units C are interconnected to form a plurality of connected ring topological connections.

[0061] Specifically, based on the ring topology connection between the sampling units C in the battery control module B, the sampling units C are connected to each other so that n sampling units C form a plurality of connected ring topology connections. Figure 4 Taking B1 as an example, the sampling unit C includes C11, C12, C13, C14, C15, and C16. On the basis of C11, C12, C13, C14, C15, and C16 being connected in sequence to form a ring topology connection, C15 and C12 are connected to form two adjacent ring topology connections. Figure 5When the communication between C11 and C12 is disconnected, the communication direction is C11-C16-C15-C14-C13-C12-C15-C16-C11. Therefore, compared with the method of looping from C11 to C12 and then from C12 back to C11, the communication route is saved, and thus the sampling time is saved.

[0062] In some optional embodiments, the slave battery control modules B are connected in series via a sampling unit C.

[0063] Specifically, a redundant design is adopted between the sampling units C of each slave battery control module B. The sampling unit C of B1 is connected to the sampling unit C of B2, the sampling unit C of B2 is connected to the sampling unit C of B3, and so on. Therefore, if the communication connection between the sampling unit C of the slave battery control module B and the master battery control module A is disconnected, the battery data is collected through the communication connection between the slave battery control modules B.

[0064] It is worth noting that the slave battery control modules B are connected in parallel, and the sampling units C of the slave battery control modules B are connected in series, thereby supporting the independent communication connection between each slave battery control module B and the master battery control module A, and also supporting the communication connection between each slave battery control module B, that is, the daisy chain communication nodes are flexibly combined in series and parallel modes, which reduces the overall cost of the system, simplifies the complexity of the system design, reduces the sampling cycle, shortens the sampling time, and greatly increases the fault tolerance and operability of the system.

[0065] In some optional embodiments, such as Figure 6 As shown, the first sampling unit of the mth slave battery control module is connected to the nth sampling unit of the m-1th slave battery control module, where m>1.

[0066] Specifically, refer to Figure 6 , C21 is connected to C1n, C31 is connected to C2n, and so on. Therefore, if C11 is disconnected from the master battery control module A, C21 receives the sampling instruction sent by the master battery control module A and simultaneously sends the sampling instruction to C1n and C22. C1n sends the first to nth battery data collected by C11, C12, ..., C1n to C21, and C21 sends the battery data of C11, C12, ..., C1n together with the battery data of C21, C22, ..., C2n to the master battery control module A. Thus, when the sampling unit C in the slave battery control module B is disconnected from the master battery control module A, the problem of transmitting the sampling instruction and battery data is solved.

[0067] refer to Figure 7When the two-way communication connection between the slave battery control module B and the master battery control module A is complete, the master battery control module A sends sampling instructions to C11, C21, and Cm1 respectively. C11 sends all the battery data of B1 to the master battery control module A, and C21 sends all the battery data of B2 to the master battery control module A, and so on. Figure 8 If the bidirectional communication connection between B2 through Bm and the master battery control module A is disconnected, the master battery control module A and each sampling unit transmit battery data in a serial connection. That is, C1n transmits battery data from C11, C12, ...C1n to C21, C2n transmits battery data from C11, C12, ...C1n and C21, C22, ...C2n to C31, and so on. It should be noted that if a communication node in a sampling unit experiences a communication interruption or other failure, this does not affect data transmission from the upstream sampling unit. The sampling unit can still transmit data in the reverse direction to the upstream sampling unit and can also select another path to continue communication with the downstream sampling unit. For example, if communication between C13 and C14 fails, C21 can transmit sampling instructions to C1n, and C1n transmits the sampling instructions to C14.

[0068] In some optional embodiments, such as Figure 9 As shown, the main battery control module A includes: a communication unit A1 and a main control unit A2;

[0069] The first end of the communication unit A1 is connected to the main control unit A2, and the second end of the communication unit A1 is connected to the slave battery control module B. The communication unit A1 is used to send sampling instructions to the slave battery control module B and send sampled battery data to the main control unit A2.

[0070] Specifically, when the main control unit A2 sends a sampling instruction to the communication unit A1, the communication unit A1 sends the sampling instruction to B1 to Bm respectively. The communication unit A1 receives the battery data sent by each target sampling unit and sends the battery data to the main control unit A2.

[0071] In some optional implementations, the communication unit A1 includes:

[0072] Bidirectional bridge chip, the bidirectional bridge chip is connected to the main control unit A2 and the slave battery control module B respectively, and the bidirectional bridge chip is used to send sampling instructions to the slave battery control module B, and send the sampled battery data to the main control unit A2.

[0073] Specifically, compared to the traditional parallel communication method in which each slave battery control module B needs to be equipped with a bridge chip, the battery management system provided by the present invention only needs to be equipped with a bidirectional bridge chip, which greatly reduces the cost of the bridge chip.

[0074] In some optional embodiments, the communication unit includes: a first bridge chip and a second bridge chip;

[0075] The first bridge chip is connected to each slave battery control module B and the main control unit A2 respectively, and the first bridge chip is used to send sampling instructions to each slave battery control module B;

[0076] The second bridge chip is connected to each slave battery control module B and the main control unit A2 respectively. The second bridge chip is used to send the battery data of each slave battery control module B to the main control unit A2.

[0077] Specifically, the main control unit A2 sends the sampling instructions to each slave battery control module B through the first bridge chip, and each slave battery control module B sends the sampled battery data to the main control unit A2 through the second bridge chip.

[0078] In addition, the main control unit A2 sends the sampling instruction to the first slave battery control module through the first bridge chip, and the main control unit A2 and each sampling unit send battery data in a series connection manner, that is, C1n sends the battery data of C11, C12...C1n to C21, C2n sends the battery data of C11, C12...C1n and C21, C22...C2n to C31, and so on. Finally, Cmn in the mth slave battery control module sends the battery data of C11, C12...C1n, C21, C22...C2n,...Cm1, Cm2...Cmn to the main control unit A2 through the second bridge chip.

[0079] In some optional embodiments, such as Figure 10 As shown, each sampling unit C is connected to one or more battery cells K, and the sampling unit C collects battery data of the one or more battery cells K.

[0080] Specifically, each sampling unit C collects battery data of one battery cell K, or each sampling unit C collects battery data of multiple battery cells K respectively.

[0081] In this embodiment, the utility model provides an electric vehicle, including the battery management system and battery as described above. Since each slave battery control module in the battery management system sends the battery data of the sampling unit to the master battery control module respectively, the sampling time is saved, thereby greatly saving the sampling cycle.

[0082] Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations shall fall within the scope defined by the appended claims.

Claims

1. A battery management system, characterized in that: The system includes: a master battery control module and m slave battery control modules, wherein m≥1; m said slave battery control modules are connected in parallel, and the said master battery control module is respectively connected to each of the said slave battery control modules for bidirectional communication, wherein the said master battery control module is used to send a sampling instruction to the said slave battery control module, and the said slave battery control module is used to send the sampled battery data to the said master battery control module; Each of the slave battery control modules includes n sampling units, where n>1; The target sampling unit is connected to the main battery control module, and is used to send the battery data collected by each sampling unit to the main battery control module, wherein the target sampling unit is any one of the n sampling units.

2. The system according to claim 1, wherein: The sampling units are connected in a ring topology, and the first sampling unit is connected to the main battery control module as a target sampling unit; The first sampling unit receives the sampling instruction, collects the first battery data, and sends the first battery data to the second sampling unit; The second sampling unit collects the second battery data, and sends the first battery data and the second battery data to the third sampling unit; Until the nth sampling unit sends the first battery data to the nth battery data to the first sampling unit, the first sampling unit sends each battery data to the main battery control module.

3. The system according to claim 2, characterized in that The sampling units are connected to each other to form a plurality of connected ring topological connections.

4. The system according to claim 1, wherein: The slave battery control modules are connected in series through the sampling unit.

5. The system according to claim 4, characterized in that The first sampling unit of the mth slave battery control module is connected to the nth sampling unit of the m-1th slave battery control module, where m>1.

6. The system according to claim 1, wherein: The main battery control module includes: a communication unit and a main control unit; The first end of the communication unit is connected to the main control unit, and the second end of the communication unit is connected to the slave battery control module. The communication unit is used to send the sampling instruction to the slave battery control module and send the sampled battery data to the main control unit.

7. The system according to claim 6, characterized in that The communication unit includes: A bidirectional bridge chip is connected to the main control unit and the slave battery control module respectively, and is used to send the sampling instruction to the slave battery control module and send the sampled battery data to the main control unit.

8. The system according to claim 6, wherein: The communication unit includes: a first bridge chip and a second bridge chip; The first bridge chip is connected to each of the slave battery control modules and the main control unit respectively, and the first bridge chip is used to send a sampling instruction to each of the slave battery control modules; The second bridge chip is connected to each slave battery control module and the main control unit respectively, and the second bridge chip is used to send the battery data of each slave battery control module to the main control unit.

9. The system according to claim 1, wherein: Each of the sampling units is connected to one or more battery cells, and the sampling unit is used to collect battery data of the one or more battery cells.

10. An electric vehicle, characterized in that: The electric vehicle comprises the battery management system according to any one of claims 1 to 9.

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