Wireless battery pack management system

Abstract

The invention relates to the technical field of battery pack management, and discloses a wireless battery pack management system, and the system comprises a battery control module which is used for executing task scheduling, vehicle request response, wireless network management and activity keeping mode control; a module monitoring module, a diagnosis marking module and a safety control module; and the wireless main node and the wireless equipment node form a star wireless network and support data communication between the battery control unit and the battery sensing unit. According to the invention, wire harnesses are replaced by wireless connection, so that most of fault sources caused by connector corrosion, vibration loosening, port aging and wire harness abrasion are eliminated, and the overall connection reliability of the system is remarkably improved; through reverse battery protection, multi-stage over-current detection, high-voltage interlocking and insulation resistance monitoring, a multi-layer and deep defense system which receives internal overload by mistake from the outside and converts connection integrity to electrical isolation integrity is constructed, and personal and component safety is effectively guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery pack management, in particular to a wireless battery pack management system. BACKGROUND

[0002] With the rapid development of electric vehicles and hybrid electric vehicles, the battery management system as the "brain" of the power battery pack, its performance and reliability are directly related to the safety, range and battery life of the vehicle. The traditional battery management system generally adopts a wired communication architecture, especially a wired connection mode based on "daisy chain", which connects the battery control unit and the battery sensing unit distributed in each battery module to collect key parameters such as voltage and temperature.

[0003] However, this traditional wired BMS architecture has several inherent technical defects: First, the system reliability is challenged. The numerous wiring harnesses, connectors and complex wiring constitute potential failure points of the system. In the long-term vibration, high and low temperature cycle and humid environment of the vehicle, the connectors are prone to corrosion or poor contact, and the wiring harnesses may break due to wear or aging, resulting in data communication interruption or acquisition distortion, which seriously affects the reliability of the BMS, and may even cause false protection.

[0004] Second, the system cost, weight and manufacturing complexity are high. The dedicated high-voltage isolation communication wiring harness and its connector are expensive. At the same time, a large number of wiring harnesses increase the overall weight of the battery pack, which indirectly affects the vehicle range. In terms of manufacturing, the wiring of the wiring harness and the connector insertion require a large amount of manual operation, which not only increases the production cost, but also prolongs the production cycle, becoming one of the bottlenecks of the automatic production of the battery pack.

[0005] Third, the system layout flexibility is poor. The length and direction of the wired connection are fixed, which seriously limits the optimization design of the battery module arrangement in the battery pack. When the battery pack capacity needs to be adjusted or the structure design needs to be changed, the wiring harness layout often needs to be redesigned, lacking modularity and scalability.

[0006] Fourth, maintenance and replacement are difficult. When a battery module or sensing unit fails, the entire wiring harness connected to it may need to be removed or replaced, with a complex maintenance process and high cost.

[0007] To overcome the drawbacks of wired connection, the industry has begun to explore wireless battery management systems. Some existing wireless BMS solutions attempt to use general wireless communication protocols (such as Bluetooth, Zigbee, etc.) for data transmission. However, these solutions often have the following shortcomings: Insufficient real-time and reliability: general protocols are not designed for the stringent real-time and reliability requirements of BMS, making it difficult to ensure low-latency, high-success-rate transmission of all node data in a harsh vehicle electromagnetic environment.

[0008] Power consumption and security challenges: the power consumption of continuous monitoring of communication is high, which is not conducive to energy preservation when the vehicle is stationary; its security mechanism is also difficult to fully meet the requirements of the highest level of automotive functional safety (such as ASIL-D).

[0009] Low degree of functional integration: most of them focus on solving communication problems and fail to deeply integrate and systematically optimize the advantages of wireless and the core functions of battery management (such as efficient balancing, intelligent charging, comprehensive high-voltage safety diagnosis, thermal management failure monitoring, etc.). SUMMARY

[0010] The purpose of the present application is to provide a wireless battery pack management system to solve the problems raised in the background art.

[0011] To achieve the above-mentioned purpose, the present application provides the following technical solutions: The wireless battery pack management system comprises: Battery control module: for performing task scheduling, vehicle request response, wireless network management and active mode control; Module monitoring module: for monitoring the state of the main contactor, the voltage of the battery pack, the bus voltage, the pre-charging program and the pre-charging resistance temperature; Diagnosis marking module: for recording and reporting system voltage abnormalities, communication loss, contactor failure, high-voltage interlock failure, pre-charging time abnormalities and diagnosis failures of the cooling system; Safety control module: for performing battery thermal management, battery protection, battery balancing control, electrical hazard protection, high-voltage interlock and high-voltage control; Wireless master node and wireless device node: constitute a star-shaped wireless network to support data communication between the battery control unit and the battery sensing unit.

[0012] As a further scheme of the present application, it further comprises: Communication error detection module: for preventing data damage, duplication, loss, delay, insertion and disguise threats through time stamp, timeout mechanism, source and target identifier, security code and encryption technology; Anti-interference module: adopts frequency hopping communication mode to resist random and intentional radio frequency interference.

[0013] As a further scheme of the present application, it further comprises: Energy distribution module: for realizing the distribution and management of battery energy; and through the diagnosis marking module and the communication error detection module, the system state and communication integrity in the energy distribution process are continuously monitored; Charging management module: for realizing the control of slow charging of the on-board charger and fast charging of the charging pile; during the whole charging process, the consistency of the single battery voltage and temperature is continuously monitored; For slow charging: adopt multi-stage constant current-constant voltage charging strategy, initially charge with a large constant current, switch to constant voltage mode when the voltage approaches the cutoff voltage, and gradually reduce the current; For fast charging: when the state of charge of the battery is below a threshold, request the maximum allowed current of the charging pile for high-power constant current charging; when the state of charge of the battery exceeds the threshold, dynamically adjust the requested current and perform constant voltage charging with decreasing slope.

[0014] As a further scheme of the application: the keep-alive mode in the battery control module is a configurable ultra-low power consumption mode; and the battery control module dynamically adjusts the parameters of the keep-alive mode according to the current state of charge of the battery or the vehicle operating scenario; The battery balancing control unit in the safety control module supports passive balancing and active balancing.

[0015] As a further scheme of the application: the module monitoring module also implements reverse battery protection, overcurrent detection, and high-voltage diagnosis

[0016] The safety control module also implements high-voltage interlock detection, insulation resistance monitoring, and coolant leakage detection.

[0017] As a further scheme of the application: the module monitoring module includes: a voltage acquisition circuit for acquiring the voltages of multiple battery cells; a temperature acquisition circuit for acquiring data from multiple temperature sensors; The module monitoring module communicates with the battery control module through a wireless method, or is connected through a daisy chain in a wired backup mode.

[0018] As a further scheme of the application: the battery control module includes: a multi-channel communication interface supporting CAN 2.0B, CAN FD, Ethernet, SPI, and RS232; a high-voltage isolation circuit for achieving electrical isolation between high voltage and low voltage.

[0019] As a further scheme of the application: the control method of the system includes the following steps: S1, scheduling system tasks and managing wireless network status through the battery control module; and dynamically switching between active mode and keep-alive mode according to system load to optimize system power consumption; S2, real-time acquisition of battery voltage, current, and contactor status through the module monitoring module; S3, detecting system faults and generating diagnostic fault codes through the diagnostic flag module; S4, performing frequency hopping communication through the anti-interference module to resist external interference; S5, checking data integrity by a communication error detection module, triggering a retransmission mechanism; S6, implementing battery protection and thermal management strategies by a safety control module.

[0020] Compared with the prior art, the present application has the following beneficial effects: The present application replaces the wiring harness with wireless connection, eliminating most of the failure sources caused by connector corrosion, vibration loosening, port aging and wiring harness wear, and significantly improving the overall connection reliability of the system; through the star-shaped wireless topology, the system is not affected by single point failure; Through reverse battery protection, multi-stage overcurrent detection, high-voltage interlocking and insulation resistance monitoring, a multi-level and in-depth defense system is constructed from external misconnection to internal overload, from connection integrity to electrical isolation integrity, effectively protecting personal and component safety; Through strong anti-interference and error detection mechanism to ensure communication safety; through low power consumption to maintain active mode to prolong system standby time. BRIEF DESCRIPTION OF DRAWINGS

[0021] Fig. 1 It is a structural schematic diagram of a wireless battery pack management system; Fig. 2 It is a working process schematic diagram of a wireless battery pack management system. DETAILED DESCRIPTION

[0022] Please refer to Figs. 1-2 In the embodiment of the present application, the wireless battery pack management system comprises: Battery control module: for performing task scheduling, vehicle request response, wireless network management and active mode control; Module monitoring module: for monitoring the state of the main contactor, the voltage of the battery pack, the bus voltage, the pre-charging program and the pre-charging resistance temperature; Diagnosis marking module: for recording and reporting system voltage abnormalities, communication loss, contactor failure, high-voltage interlocking failure, pre-charging time abnormalities and cooling system diagnosis failure; Safety control module: for performing battery thermal management, battery protection, battery balance control, electrical hazard protection, high-voltage interlocking and high-voltage control; Wireless master node and wireless device node: constitute a star-shaped wireless network, support data communication between battery control unit and battery sensing unit; wireless network adopts time division multiple access mechanism, including downlink and multiple uplink time slots, supports transmission of data from each node every 100 milliseconds, data rate is not less than 2 Mbps, adopts AES-128 / 256 encryption, and supports multi-master device redundancy and wireless software update, and only updates application image to reduce verification overhead; average current of wireless master node <100μA, average current of wireless device node <70μA.

[0023] Preferably, it also includes: Communication error detection module: for preventing data damage, duplication, loss, delay, insertion and disguise threats through timestamp, timeout mechanism, source and target identifier, security code and encryption technology; and supporting transmission code checker triggering data retransmission; compared with wired system, wireless is more vulnerable to data damage caused by interference, and wireless hardware failure rate increases total link failure rate; reasons for wireless communication error include damage, accidental duplication, incorrect sequence, loss, unacceptable delay, insertion and disguise; threats formed include duplicate deletion, insertion, reordering, damage, delay and disguise; therefore, communication error detection mechanism improves security to reduce overall error rate of transmission medium; Anti-interference module: adopts frequency hopping communication mode to resist random and intentional radio frequency interference; such as supporting 40 channel frequency hopping in 2.4GHz frequency band, network resynchronization time is not more than 109 milliseconds, and has anti-WiFi and BLE interference capability, in WiFi and BLE interference environment, system throughput decreases by not more than 5%, and packet error rate (PER=number of error data packets / total number of data packets x 100%) is not more than 1 ³.

[0024] Preferably, it also includes: Energy allocation module: for realizing allocation and management of battery energy; and continuously monitoring system state and communication integrity in energy allocation process through diagnosis marking module and communication error detection module; if it is detected that the allocation effect deviates from the expectation or a fault occurs, triggering strategy recalculation to realize closed-loop control and adaptive optimization; under the premise of ensuring safety and service life, intelligently coordinating driving, charging and vehicle-mounted energy consumption to ensure vehicle power response and charging speed; Charging management module: for realizing control of slow charging of vehicle-mounted charger and fast charging of charging pile; continuously monitoring consistency of single battery voltage and temperature during the whole charging process; if it is found that any single voltage or temperature is close to the safety threshold, immediately dynamically reducing the charging current or suspending the charging; through dynamically adjusted charging curve, under the premise of ensuring battery safety and service life, the acceptable charging capacity of the battery is maximized to shorten the fast charging time; For slow charging: adopt multi-stage constant current-constant voltage charging strategy, initially charge with a large constant current, switch to constant voltage mode when the voltage approaches the cutoff voltage, and gradually reduce the current; For fast charging: when the battery state of charge (SOC) is below a threshold (such as 80%), request the maximum allowed current (CCL) of the charging pile for high-power constant current charging; when the battery state of charge exceeds the threshold, dynamically adjust the requested current and perform constant voltage charging with a decreasing slope to avoid lithium precipitation and reduce battery polarization.

[0025] Preferably, the keep-alive mode in the battery control module is a configurable ultra-low power mode that supports dynamic adjustment of the system between power and performance; and the battery control module dynamically adjusts the parameters of the keep-alive mode according to the current state of charge of the battery or the vehicle operating scenario; for example, when the battery SOC is low, the keep-alive interval is automatically extended to prioritize energy saving; when the vehicle is in a charging preparation state or a suspected fault state, the interval is shortened to improve network response performance; The system always listens for external wake-up events during the keep-alive mode; once events such as vehicle key wake-up signals, CAN bus charging requests, or diagnostic instructions are detected, the keep-alive mode is terminated immediately, all nodes are fully awakened, and a high-throughput active network is reconstructed within 300 milliseconds to restore normal communication and data processing capabilities.

[0026] The battery balancing control unit in the safety control module supports passive balancing and active balancing, with a balancing current not less than 300mA; During passive balancing, the voltage or state of charge of the target cell is continuously monitored; when the deviation from the average value decreases to within the preset balance termination threshold, the corresponding bypass switch is closed and the balancing is stopped; and the duration and energy dissipation of this balancing are recorded for updating the battery historical data; During active balancing, when the voltage or state of charge of all cells reaches the preset consistency target, or the maximum balancing time is reached, or any system abnormality is detected, the energy transfer is terminated; by reducing the energy variance of the entire battery pack, the available capacity and output power capability of the system are directly improved.

[0027] Preferably, the module monitoring module also implements reverse battery protection, overcurrent detection, and high voltage diagnosis; during reverse battery protection, once the fault is established, the system immediately executes protective lockout: prohibits all high-voltage contactor (including main positive, main negative, and pre-charge contactor) closing instructions, and generates the highest priority DTC (diagnostic fault code) and warning information through the diagnostic marker module, sending them to the vehicle instrument panel to prompt the user to check the connection; During overcurrent detection, according to the fault level, perform graded protection actions: For recoverable overcurrent, the system coordinates the vehicle control unit (VCU) to smoothly reduce the output power; For non-recoverable overcurrent or transient peak overcurrent, the system immediately issues a command to forcibly open all high-voltage contactors, achieving millisecond-level hardware protection; During high-voltage diagnosis, according to the diagnosis results, the system should enter the following safe states: For insulation failure, immediately open the contactor and prohibit power-up; For contactor sticking, record the DTC and prohibit the next start, or enter the degraded operation mode; For pre-charge failure, terminate the start process and report the specific fault reason; The safety control module also implements high-voltage interlock detection, insulation resistance monitoring, and coolant leakage detection; during high-voltage interlock detection, once a high-voltage interlock fault is detected, the system immediately prohibits all high-voltage contactors from closing; if the fault occurs while the system is already powered on and running, the highest priority alarm is triggered, and the vehicle controller is requested to enter the reduced power operation or safe parking process; During insulation resistance monitoring, according to the severity of the insulation resistance drop, a graded response is executed: For mild drop, record the DTC and limit system functions; For severe drop or below the minimum threshold, immediately open the high-voltage contactor to achieve electrical isolation, and generate an emergency alarm; During coolant leakage detection, after confirming the leakage, the system performs: Immediately request the thermal management system to stop the coolant circulation pump to prevent the leakage from expanding; Generate a high-priority DTC and a maintenance alarm, clearly indicating "cooling system leakage"; In severe leakage cases, it can be recommended to limit battery charging and discharging power to control heat generation.

[0028] Preferably, the module monitoring module includes: A voltage acquisition circuit for acquiring the voltage of multiple battery cells with a precision better than ±2mV; A temperature acquisition circuit for acquiring data from multiple temperature sensors with a precision better than ±1°C; The module monitoring module communicates with the battery control module through wireless means, or through daisy chain connection in wired backup mode.

[0029] Preferably, the battery control module includes: A multi-channel communication interface supporting CAN 2.0B, CAN FD, Ethernet, SPI, and RS232; A high-voltage isolation circuit for electrical isolation between high voltage and low voltage; And the firmware supports UDS diagnostic protocol, OTA wireless update and NVM data storage.

[0030] Preferably, as shown in the figure, the control method of the system comprises the following steps: Fig. 2 S1, scheduling system tasks and managing wireless network status through the battery control module; and dynamically switching active mode and standby mode according to system load to optimize system power consumption; S2, collecting battery voltage, current and contactor status in real time through the module monitoring module; S3, detecting system faults and generating diagnostic fault codes through the diagnostic flag module; S4, performing frequency hopping communication through the anti-interference module to resist external interference; S5, checking data integrity through the communication error detection module to trigger the retransmission mechanism; S6, implementing battery protection and thermal management strategies through the safety control module. In order to verify the safety, reliability and robustness of the system, node evaluation and interference test are carried out respectively.

[0031] The node evaluation results are shown in Table 1 below.

[0032] From Table 1, it can be concluded that the received signal strength indication (RSSI) and the number of retries from the wireless master (WM) to the wireless device (WD) increase with the increase of obstacles and layout.

[0033] The interference test detects throughput and delay, and the results are shown in Table 2 below.

[0034] From Table 2, it can be concluded that in the interference test, for different packet sizes, the throughput is reduced by at most 5% when there is interference; the delay is small, and the system network can still run completely when it is interfered.

[0035] The above is only the preferred specific implementation of the present application, but the protection scope of the present application is not limited thereto, any skilled person in the art can make equivalent replacement or change according to the technical solution and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.​

Claims

1. A wireless battery pack management system, characterized by, The system comprises: a battery control module for performing task scheduling, vehicle request response, wireless network management, and keeping active mode control; a module monitoring module for monitoring main contactor status, battery pack voltage, bus voltage, pre-charge program, and pre-charge resistance temperature; a diagnostic marking module for recording and reporting system voltage abnormalities, communication loss, contactor failure, high-voltage interlock failure, pre-charge time abnormalities, and diagnostic failures of the cooling system; a safety control module for performing battery thermal management, battery protection, battery balancing control, electrical hazard protection, high-voltage interlock, and high-voltage control; a wireless master node and a wireless device node to form a star-shaped wireless network to support data communication between the battery control unit and the battery sensing unit.

2. The wireless battery pack management system of claim 1, wherein, Further comprising: a communication error detection module for preventing data damage, duplication, loss, delay, insertion, and disguise threats through time stamping, timeout mechanism, source and target identifiers, security code, and encryption technology; an anti-interference module using frequency hopping communication mode to resist random and intentional radio frequency interference.

3. The wireless battery pack management system of claim 1, wherein, Further comprising: an energy distribution module for implementing battery energy distribution and management; and through the diagnostic marking module and the communication error detection module, the system state and communication integrity during the energy distribution process are continuously monitored; a charging management module for controlling the slow charging of the on-board charger and the fast charging of the charging pile; during the entire charging process, the consistency of the single battery voltage and temperature is continuously monitored; for slow charging: a multi-stage constant current-constant voltage charging strategy is adopted, the initial charging is carried out with a large constant current, and when the voltage approaches the cut-off voltage, the charging mode is switched to constant voltage, and the current is gradually reduced; for fast charging: when the state of charge of the battery is below a threshold value, the maximum allowed current of the charging pile is requested for high-power constant current charging; when the state of charge of the battery exceeds the threshold value, the requested current is dynamically adjusted to perform constant voltage charging with a decreasing slope.

4. The wireless battery pack management system of claim 1, wherein, The keep-alive mode in the battery control module is a configurable ultra-low power mode; and the parameters of the keep-alive mode are dynamically adjusted by the battery control module according to the current state of charge of the battery or the vehicle operating scenario; the battery balancing control unit in the safety control module supports passive balancing and active balancing.

5. The wireless battery pack management system of claim 1, wherein, The module monitoring module also implements reverse battery protection, overcurrent detection, and high-voltage diagnosis The safety control module also implements high-voltage interlock detection, insulation resistance monitoring, and cooling liquid leakage detection.

6. The wireless battery pack management system of claim 1, wherein, The module monitoring module comprises: a voltage acquisition circuit for acquiring the voltage of multiple battery cells; a temperature acquisition circuit for acquiring data from multiple temperature sensors; The module monitoring module communicates with the battery control module through a wireless mode, or is connected in a wired backup mode through a daisy chain.

7. The wireless battery pack management system of claim 1, wherein, The battery control module comprises: a multi-channel communication interface supporting CAN 2.0B, CAN FD, Ethernet, SPI, and RS232; a high-voltage isolation circuit for electrical isolation between high voltage and low voltage.

8. The wireless battery pack management system of claim 1, wherein, The control method of the system comprises the following steps: S1, scheduling system tasks and managing wireless network status through the battery control module; and dynamically switching between active mode and keep-alive mode according to system load to optimize system power consumption; S2, real-time acquisition of battery voltage, current and contactor state through the module monitoring module; S3, detecting system faults and generating diagnostic fault codes through the diagnostic marking module; S4, performing frequency hopping communication through the anti-interference module to resist external interference; S5, checking data integrity through the communication error detection module to trigger the retransmission mechanism; S6, implementing battery protection and thermal management strategies through the safety control module.

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